chore(tox): remove psycopg2 from requirements

This package is already in the test image.
4 jobs for branch/default in 55 seconds (queued for 9 seconds)
Name Stage Failure
failed
py3 Tests
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py3-deprecated-warnings.json: found 1 matching files and directories

Uploading artifacts as "archive" to coordinator... ok
id=475277 responseStatus=201 Created token=1ZLZAeG7
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report.xml: found 1 matching files and directories

Uploading artifacts as "junit" to coordinator... ok
id=475277 responseStatus=201 Created token=1ZLZAeG7
Cleaning up file based variables
ERROR: Job failed: command terminated with exit code 1