[MAINTENANCE] Update all repos to main branch

[ByteOtter]

What this PR does / why we need it:

Now that most repos had their docs-ng branch merged to main, this PR updates the repo-config.json file accordingly.

Which issue(s) this PR fixes:
Fixes # -

Definition of Done:

• The code is sufficiently documented
• Shared the changes with the Team so everyone is aware
• The code is appropriately tested
• Checked if the code needs to be backportet to release branches of maintained versions (perform the actual backport after the merge to main)

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