docs: clarify that token properties don't extend beyond the action (#204

)

README.md

@@ -131,7 +131,8 @@ risk.**
 
 The following inputs are for _generating_ OAuth 2.0 access tokens for
 authenticating to Google Cloud as an output for use in future steps in the
-workflow. By default, this action does not generate any tokens.
+workflow. These options only apply to access tokens generated by this action. By
+default, this action does not generate any tokens.
 
 -   `token_format`: This value must be `"access_token"` to generate OAuth 2.0
     access tokens. To skip token generation, omit or set to the empty string "".
@@ -172,8 +173,9 @@ workflow. By default, this action does not generate any tokens.
 ### Generating ID tokens
 
 The following inputs are for _generating_ ID tokens for authenticating to Google
-Cloud as an output for use in future steps in the workflow. By default, this
-action does not generate any tokens.
+Cloud as an output for use in future steps in the workflow. These options only
+apply to ID tokens generated by this action. By default, this action does not
+generate any tokens.
 
 -   `token_format`: This value must be `"id_token"` to generate ID tokens. To
     skip token generation, omit or set to the empty string "".