chore: regens API reference docs (#889)

diff --git a/docs/dyn/container_v1beta1.projects.locations.html b/docs/dyn/container_v1beta1.projects.locations.html
index 66d1a3a..8ee4049 100644
--- a/docs/dyn/container_v1beta1.projects.locations.html
+++ b/docs/dyn/container_v1beta1.projects.locations.html
@@ -98,12 +98,13 @@
 Args:
   name: string, The name (project and location) of the server config to get,
 specified in the format 'projects/*/locations/*'. (required)
-  projectId: string, Deprecated. The Google Developers Console [project ID or project
+  projectId: string, Required. Deprecated. The Google Developers Console [project ID or project
 number](https://support.google.com/cloud/answer/6158840).
 This field has been deprecated and replaced by the name field.
-  zone: string, Deprecated. The name of the Google Compute Engine
-[zone](/compute/docs/zones#available) to return operations for.
-This field has been deprecated and replaced by the name field.
+  zone: string, Required. Deprecated. The name of the Google Compute Engine
+[zone](https://cloud.google.com/compute/docs/zones#available) to return
+operations for. This field has been deprecated and replaced by the name
+field.
   x__xgafv: string, V1 error format.
     Allowed values
       1 - v1 error format
@@ -113,17 +114,30 @@
   An object of the form:
 
     { # Kubernetes Engine service configuration.
-    "defaultClusterVersion": "A String", # Version of Kubernetes the service deploys by default.
     "validNodeVersions": [ # List of valid node upgrade target versions.
       "A String",
     ],
+    "defaultImageType": "A String", # Default image type.
+    "defaultClusterVersion": "A String", # Version of Kubernetes the service deploys by default.
+    "validMasterVersions": [ # List of valid master versions.
+      "A String",
+    ],
+    "channels": [ # List of release channel configurations.
+      { # ReleaseChannelConfig exposes configuration for a release channel.
+        "defaultVersion": "A String", # The default version for newly created clusters on the channel.
+        "channel": "A String", # The release channel this configuration applies to.
+        "availableVersions": [ # List of available versions for the release channel.
+          { # AvailableVersion is an additional Kubernetes versions offered
+              # to users who subscribed to the release channel.
+            "reason": "A String", # Reason for availability.
+            "version": "A String", # Kubernetes version.
+          },
+        ],
+      },
+    ],
     "validImageTypes": [ # List of valid image types.
       "A String",
     ],
-    "validMasterVersions": [ # List of valid master versions.
-      "A String",
-    ],
-    "defaultImageType": "A String", # Default image type.
   }</pre>
 </div>
 
@@ -132,7 +146,7 @@
   <pre>Fetches locations that offer Google Kubernetes Engine.
 
 Args:
-  parent: string, Contains the name of the resource requested.
+  parent: string, Required. Contains the name of the resource requested.
 Specified in the format 'projects/*'. (required)
   x__xgafv: string, V1 error format.
     Allowed values