Description

Added Google OAuth2 authentication feature using the access_token or id_token.

Type of change

[x] Added a new endpoint for authenticating using Google (api_token or access_token). New endpoint is: /wp-json/jwt-auth/v1/google_auth.
[x] The new endpoint receives two parameters (type and token). Where type can be either access_token or id_token, and token is the response received from Google OAuth2.
[x] Updated code for a more efficient way to access user information before sending data as API response.
[x] Updated $user->data->ID, $user->data->user_email, $user->data->user_nicename, $user->data->display_name to $user->ID, $user->user_email, $user->user_nicename, $user->display_name.

[x] Used Postman Software for testing the new API endpoint using both access_token and id_token.
[x] Checked error handling by testing without parameters and with wrong token.
[x] After all test cases, verified the API response using /wp-json/jwt-auth/v1/token/validate and it works fine.

Test Configuration:

[x] My code follows the style guidelines of this project (WordPress code standards).
[x] I have performed a self-review of my own code.
[x] I have commented on my code, particularly in hard-to-understand areas.
[x] I have made corresponding changes to the documentation (if needed).
[x] My changes generate no new warnings.
[x] I have described how I made my tests that prove my fix is effective or that my feature works.