Schema and read endpoints Pool

[OmairK]

Closes #8131

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[mik-laj]

Perfect. I merge it when I get permission from Kaxil.
https://apache-airflow.slack.com/archives/CCPRP7943/p1591962654060300

[mik-laj]

Github Action is sad. I think these are a flaky tests. However, to be sure, could you do a rebase? Over 3 red crosses are not good.

[OmairK]

Github Action is sad. I think these are a flaky tests. However, to be sure, could you do a rebase? Over 3 red crosses are not good.

All the api_connexion tests are passing now.
Just one test is failing

tests/www/test_views.py

[mik-laj]

@OmairK Can you do a rebase? We fixed test_views.py. #9307