chore: regens API reference docs (#889)

diff --git a/docs/dyn/tagmanager_v2.accounts.containers.version_headers.html b/docs/dyn/tagmanager_v2.accounts.containers.version_headers.html
index 997cc01..1a43bfe 100644
--- a/docs/dyn/tagmanager_v2.accounts.containers.version_headers.html
+++ b/docs/dyn/tagmanager_v2.accounts.containers.version_headers.html
@@ -75,50 +75,60 @@
 <h1><a href="tagmanager_v2.html">Tag Manager API</a> . <a href="tagmanager_v2.accounts.html">accounts</a> . <a href="tagmanager_v2.accounts.containers.html">containers</a> . <a href="tagmanager_v2.accounts.containers.version_headers.html">version_headers</a></h1>
 <h2>Instance Methods</h2>
 <p class="toc_element">
-  <code><a href="#latest">latest(parent)</a></code></p>
+  <code><a href="#latest">latest(parent, x__xgafv=None)</a></code></p>
 <p class="firstline">Gets the latest container version header</p>
 <p class="toc_element">
-  <code><a href="#list">list(parent, includeDeleted=None, pageToken=None)</a></code></p>
+  <code><a href="#list">list(parent, includeDeleted=None, pageToken=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Lists all Container Versions of a GTM Container.</p>
 <p class="toc_element">
   <code><a href="#list_next">list_next(previous_request, previous_response)</a></code></p>
 <p class="firstline">Retrieves the next page of results.</p>
 <h3>Method Details</h3>
 <div class="method">
-    <code class="details" id="latest">latest(parent)</code>
+    <code class="details" id="latest">latest(parent, x__xgafv=None)</code>
   <pre>Gets the latest container version header
 
 Args:
-  parent: string, GTM Container's API relative path. Example: accounts/{account_id}/containers/{container_id} (required)
+  parent: string, GTM Container's API relative path.
+Example: accounts/{account_id}/containers/{container_id} (required)
+  x__xgafv: string, V1 error format.
+    Allowed values
+      1 - v1 error format
+      2 - v2 error format
 
 Returns:
   An object of the form:
 
     { # Represents a Google Tag Manager Container Version Header.
     "name": "A String", # Container version display name.
-    "deleted": True or False, # A value of true indicates this container version has been deleted.
+    "numCustomTemplates": "A String", # Number of custom templates in the container version.
     "numZones": "A String", # Number of zones in the container version.
     "numMacros": "A String", # Number of macros in the container version.
-    "numCustomTemplates": "A String", # Number of custom templates in the container version.
-    "numVariables": "A String", # Number of variables in the container version.
-    "numTags": "A String", # Number of tags in the container version.
+    "deleted": True or False, # A value of true indicates this container version has been deleted.
+    "containerId": "A String", # GTM Container ID.
+    "numTriggers": "A String", # Number of triggers in the container version.
     "numRules": "A String", # Number of rules in the container version.
     "containerVersionId": "A String", # The Container Version ID uniquely identifies the GTM Container Version.
     "path": "A String", # GTM Container Versions's API relative path.
-    "numTriggers": "A String", # Number of triggers in the container version.
+    "numTags": "A String", # Number of tags in the container version.
+    "numVariables": "A String", # Number of variables in the container version.
     "accountId": "A String", # GTM Account ID.
-    "containerId": "A String", # GTM Container ID.
   }</pre>
 </div>
 
 <div class="method">
-    <code class="details" id="list">list(parent, includeDeleted=None, pageToken=None)</code>
+    <code class="details" id="list">list(parent, includeDeleted=None, pageToken=None, x__xgafv=None)</code>
   <pre>Lists all Container Versions of a GTM Container.
 
 Args:
-  parent: string, GTM Container's API relative path. Example: accounts/{account_id}/containers/{container_id} (required)
+  parent: string, GTM Container's API relative path.
+Example: accounts/{account_id}/containers/{container_id} (required)
   includeDeleted: boolean, Also retrieve deleted (archived) versions when true.
   pageToken: string, Continuation token for fetching the next page of results.
+  x__xgafv: string, V1 error format.
+    Allowed values
+      1 - v1 error format
+      2 - v2 error format
 
 Returns:
   An object of the form:
@@ -128,18 +138,18 @@
     "containerVersionHeader": [ # All container version headers of a GTM Container.
       { # Represents a Google Tag Manager Container Version Header.
         "name": "A String", # Container version display name.
-        "deleted": True or False, # A value of true indicates this container version has been deleted.
+        "numCustomTemplates": "A String", # Number of custom templates in the container version.
         "numZones": "A String", # Number of zones in the container version.
         "numMacros": "A String", # Number of macros in the container version.
-        "numCustomTemplates": "A String", # Number of custom templates in the container version.
-        "numVariables": "A String", # Number of variables in the container version.
-        "numTags": "A String", # Number of tags in the container version.
+        "deleted": True or False, # A value of true indicates this container version has been deleted.
+        "containerId": "A String", # GTM Container ID.
+        "numTriggers": "A String", # Number of triggers in the container version.
         "numRules": "A String", # Number of rules in the container version.
         "containerVersionId": "A String", # The Container Version ID uniquely identifies the GTM Container Version.
         "path": "A String", # GTM Container Versions's API relative path.
-        "numTriggers": "A String", # Number of triggers in the container version.
+        "numTags": "A String", # Number of tags in the container version.
+        "numVariables": "A String", # Number of variables in the container version.
         "accountId": "A String", # GTM Account ID.
-        "containerId": "A String", # GTM Container ID.
       },
     ],
   }</pre>