Support the global_custom_queries option in init_config

[dujuku]

What does this PR do?

Motivation

Additional Notes

Review checklist (to be filled by reviewers)

• [ ] Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• [ ] PR title must be written as a CHANGELOG entry (see why)
• [ ] Files changes must correspond to the primary purpose of the PR as described in the title (small unrelated changes should have their own PR)
• [ ] PR must have changelog/ and integration/ labels attached

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[codecov[bot]]

Codecov Report

Merging #11912 (815b301) into master (3aabbae) will increase coverage by 0.00%. Report is 3470 commits behind head on master. The diff coverage is n/a.

Additional details and impacted files

Flag	Coverage Δ
postgres	91.92% <ø> (+0.25%)	:arrow_up:

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[FlorentClarret]

Closing this PR since it's still a draft, feel free to re-open it if needed 🙂