chore: update docs/dyn (#1162)

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diff --git a/docs/dyn/gmail_v1.users.messages.attachments.html b/docs/dyn/gmail_v1.users.messages.attachments.html
index 07ce06b..18b1934 100644
--- a/docs/dyn/gmail_v1.users.messages.attachments.html
+++ b/docs/dyn/gmail_v1.users.messages.attachments.html
@@ -103,10 +103,10 @@
   An object of the form:
 
     { # The body of a single MIME message part.
-    "data": "A String", # The body data of a MIME message part as a base64url encoded string. May be empty for MIME container types that have no message body or when the body data is sent as a separate attachment. An attachment ID is present if the body data is contained in a separate attachment.
-    "size": 42, # Number of bytes for the message part data (encoding notwithstanding).
-    "attachmentId": "A String", # When present, contains the ID of an external attachment that can be retrieved in a separate `messages.attachments.get` request. When not present, the entire content of the message part body is contained in the data field.
-  }</pre>
+  &quot;attachmentId&quot;: &quot;A String&quot;, # When present, contains the ID of an external attachment that can be retrieved in a separate `messages.attachments.get` request. When not present, the entire content of the message part body is contained in the data field.
+  &quot;data&quot;: &quot;A String&quot;, # The body data of a MIME message part as a base64url encoded string. May be empty for MIME container types that have no message body or when the body data is sent as a separate attachment. An attachment ID is present if the body data is contained in a separate attachment.
+  &quot;size&quot;: 42, # Number of bytes for the message part data (encoding notwithstanding).
+}</pre>
 </div>
 
 </body></html>
\ No newline at end of file