Fix Flask Login user setting for Flask 2.2 and Flask-Login 0.6.2

[potiuk]

The Google openid auth backend of ours had hard-coded way of
seting the current user which was not compatible with Flask 2.2

With Flask-login 0.6.2 the user is stored in g module of flask, where
before, it was stored in _request_ctx_stack. Unforatunately the
google_openid rather than using _update_request_context_with_user
set the user directly in context. In Flask-login 0.6.2 this stopped
working.

This change switches to use the _update_request_context_with_user
method rather than directly storing user in context which works before
and after the Flask-Login 0.6.2 change.

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[potiuk]

@mik-laj - question - i see that you were the original author of the openid integration here. Is this something to be used also beyond the scope of the experimental API ? Is this something that can be used in the new REST API as well (I am trying to understand the extent of the problem and see if this is something we should warn the users against).

[mik-laj]

I am looking at it now, but I need to refresh the Breeze first.

[mik-laj]

Tested and it works with V1 API.

[mik-laj]

To use this backend with v1 API, i executed the following commands:

export AIRFLOW__LOGGING__LOGGING_LEVEL="DEBUG"
export AIRFLOW__API__AUTH_BACKENDS="airflow.providers.google.common.auth_backend.google_openid"
export AIRFLOW__API__GOOGLE_OAUTH2_AUDIENCE="project-id-random-value.apps.googleusercontent.com"
airflow webserver

gcloud auth activate-service-account --key-file /files/data-archive-303923-85ecb6d96736.json
airflow users create --email test-airflow-openid@data-archive-303923.iam.gserviceaccount.com -f 1 -l 2 -r Admin -u u
ENDPOINT_URL="http://localhost:8080/"
export AIRFLOW__API__GOOGLE_OAUTH2_AUDIENCE=project-id-random-value.apps.googleusercontent.com
AUDIENCE=$AIRFLOW__API__GOOGLE_OAUTH2_AUDIENCE
ID_TOKEN="$(gcloud auth print-identity-token "--audiences=${AUDIENCE}")"
curl -X GET  \
    "${ENDPOINT_URL}/api/v1/pools" \
    -H 'Content-Type: application/json' \
    -H 'Cache-Control: no-cache' \
    -H "Authorization: Bearer ${ID_TOKEN}"