CI: add server tests with Postgresql

[fflorent]

Context

See this comment: https://github.com/gristlabs/grist-core/pull/1205#discussion_r1815383501

Some server tests succeeded when using sqlite but failed with postgresql. This commit runs the same tests using a postgresql database to ensure both database types are supported for these tests.

Proposed solution

Make the CI run server tests with Postgresql

Related issues

Has this been tested?

• [x] 👍 yes, I added tests to the test suite
• [ ] 💭 no, because this PR is a draft and still needs work
• [ ] 🙅 no, because this is not relevant here
• [ ] 🙋 no, because I need help

[fflorent]

When Paul has noticed this regression specific to Postgresql, we thought we may also run the tests with this database in github CI. Though it does not seem to be as easy as I first thought. We have understood from @berhalak comment that you already run server tests against this database in your internal CI. Is it possible you either open-source the tests, or share with us how you run them so we can add the same logic to the Github CI, if that makes sense to you?

Or do you think this work is not worth the effort?

[paulfitz]

Is it possible you either open-source the tests, or share with us how you run them so we can add the same logic to the Github CI, if that makes sense to you?

This is what we have:

RUN_gen_server_pg() {
  # Repeat some tests against postgres
  run with_postgres env TEST_CLEAN_DATABASE=true TEST_REDIS_URL=redis://localhost/{redis} TESTDIR=$OUTDIR/testdir \
    $BIN/mocha '_build/test/gen-server/**/*.js' '_build/core/test/gen-server/**/*.js' $MOCHA_FLAGS
}

So we repeat the gen-server tests against postgres. I don't see the server tests running against postgres. They may need modification to do so if they assume the database is a file.

These tests weren't enough to catch the IN () problem, which only showed up in a completely different battery of tests we apply to test the quality of an existing deployment.