docs: update docs (#916)

* fix: re-run script

* test: fix noxfile
diff --git a/docs/dyn/iamcredentials_v1.projects.serviceAccounts.html b/docs/dyn/iamcredentials_v1.projects.serviceAccounts.html
index 430c48a..9198489 100644
--- a/docs/dyn/iamcredentials_v1.projects.serviceAccounts.html
+++ b/docs/dyn/iamcredentials_v1.projects.serviceAccounts.html
@@ -152,6 +152,10 @@
     The object takes the form of:
 
 {
+    "audience": "A String", # Required. The audience for the token, such as the API or account that this token
+        # grants access to.
+    "includeEmail": True or False, # Include the service account email in the token. If set to `true`, the
+        # token will contain `email` and `email_verified` claims.
     "delegates": [ # The sequence of service accounts in a delegation chain. Each service
         # account must be granted the `roles/iam.serviceAccountTokenCreator` role
         # on its next service account in the chain. The last service account in the
@@ -164,10 +168,6 @@
         # character is required; replacing it with a project ID is invalid.
       "A String",
     ],
-    "audience": "A String", # Required. The audience for the token, such as the API or account that this token
-        # grants access to.
-    "includeEmail": True or False, # Include the service account email in the token. If set to `true`, the
-        # token will contain `email` and `email_verified` claims.
   }
 
   x__xgafv: string, V1 error format.
@@ -196,6 +196,7 @@
     The object takes the form of:
 
 {
+    "payload": "A String", # Required. The bytes to sign.
     "delegates": [ # The sequence of service accounts in a delegation chain. Each service
         # account must be granted the `roles/iam.serviceAccountTokenCreator` role
         # on its next service account in the chain. The last service account in the
@@ -208,7 +209,6 @@
         # character is required; replacing it with a project ID is invalid.
       "A String",
     ],
-    "payload": "A String", # Required. The bytes to sign.
   }
 
   x__xgafv: string, V1 error format.
@@ -220,8 +220,22 @@
   An object of the form:
 
     {
-    "keyId": "A String", # The ID of the key used to sign the blob.
+    "keyId": "A String", # The ID of the key used to sign the blob. The key used for signing will
+        # remain valid for at least 12 hours after the blob is signed. To verify the
+        # signature, you can retrieve the public key in several formats from the
+        # following endpoints:
+        #
+        # - RSA public key wrapped in an X.509 v3 certificate:
+        # `https://www.googleapis.com/service_accounts/v1/metadata/x509/{ACCOUNT_EMAIL}`
+        # - Raw key in JSON format:
+        # `https://www.googleapis.com/service_accounts/v1/metadata/raw/{ACCOUNT_EMAIL}`
+        # - JSON Web Key (JWK):
+        # `https://www.googleapis.com/service_accounts/v1/metadata/jwk/{ACCOUNT_EMAIL}`
     "signedBlob": "A String", # The signature for the blob. Does not include the original blob.
+        #
+        # After the key pair referenced by the `key_id` response field expires,
+        # Google no longer exposes the public key that can be used to verify the
+        # blob. As a result, the receiver can no longer verify the signature.
   }</pre>
 </div>
 
@@ -266,10 +280,24 @@
   An object of the form:
 
     {
-    &quot;keyId&quot;: &quot;A String&quot;, # The ID of the key used to sign the JWT.
+    &quot;keyId&quot;: &quot;A String&quot;, # The ID of the key used to sign the JWT. The key used for signing will
+        # remain valid for at least 12 hours after the JWT is signed. To verify the
+        # signature, you can retrieve the public key in several formats from the
+        # following endpoints:
+        #
+        # - RSA public key wrapped in an X.509 v3 certificate:
+        # `https://www.googleapis.com/service_accounts/v1/metadata/x509/{ACCOUNT_EMAIL}`
+        # - Raw key in JSON format:
+        # `https://www.googleapis.com/service_accounts/v1/metadata/raw/{ACCOUNT_EMAIL}`
+        # - JSON Web Key (JWK):
+        # `https://www.googleapis.com/service_accounts/v1/metadata/jwk/{ACCOUNT_EMAIL}`
     &quot;signedJwt&quot;: &quot;A String&quot;, # The signed JWT. Contains the automatically generated header; the
         # client-supplied payload; and the signature, which is generated using the
         # key referenced by the `kid` field in the header.
+        #
+        # After the key pair referenced by the `key_id` response field expires,
+        # Google no longer exposes the public key that can be used to verify the JWT.
+        # As a result, the receiver can no longer verify the signature.
   }</pre>
 </div>