Add OpenID Connect login support (#77)

* Add OpenID Connect login support
* Add docs for OIDC config with Google Auth
* Use Google styles for log in
- Add support for linking existing account
- Force users to sign-in with passoword first, when linking existing accounts
- Add support to create new user when using OIDC
- Add identities to user to prevent account take-ver
- Make tests mocking instead of being integration tests
- Manage session handling correctly
- use OmniAuth.config.mock_auth instead of passing auth data via request env
* Conditionally render Oauth button

- Set a config item `configuration.x.auth.oidc_enabled`
- Hide button if disabled

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Signed-off-by: Juan José Mata <juanjo.mata@gmail.com>
Signed-off-by: soky srm <sokysrm@gmail.com>
Co-authored-by: sokie <sokysrm@gmail.com>

test/test_helper.rb

@@ -36,6 +36,11 @@ VCR.configure do |config|
   config.filter_sensitive_data("<PLAID_SECRET>") { ENV["PLAID_SECRET"] }
 end
 
+# Configure OmniAuth for testing
+OmniAuth.config.test_mode = true
+# Allow both GET and POST for OIDC callbacks in tests
+OmniAuth.config.allowed_request_methods = [ :get, :post ]
+
 module ActiveSupport
   class TestCase
     # Run tests in parallel with specified workers