Gate extension routes

[aalves08]

Summary

Fixes #15645

Occurred changes and/or fixed issues

• adds logic for gating routes that aren't registered, preventing access to said pages. Especially useful for builtin extensions like SCC
• adds unit tests

Technical notes summary

Areas or cases that should be tested

• Check the SCC example in the issue Tech debt: Gate the addRoutes for extensions to follow the same conditions as configureType/virtualType #15645 /c/local/settings/registration. If SCC is not enabled, user is redirected to 404 page

Areas which could experience regressions

Screenshot/Video

Checklist

• The PR is linked to an issue and the linked issue has a Milestone, or no issue is needed
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• The PR has automated tests or clear instructions for manual tests and the linked issue has appropriate QA labels, or tests are not needed
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• The PR has considered, and if applicable tested with, the three Global Roles Admin, Standard User and User Base

[aalves08]

Back to draft since this is making e2e tests fail... needs investigation