Revert "Support Microsoft SAML attribute names by default"

Purpose of revert

Revert Support Microsoft SAML attribute names by default (!135770 - merged)

This reverts commit 3c426a56, reversing changes made to 33761759.

In e2e tests this fails because of a feature flag in an initializer. Reverting while we rework it.

Checklist

• Create an issue to reinstate the merge request and assign it to the author of the reverted merge request.
• If the revert is to resolve a broken 'master' incident, please read through the Responsibilities of the Broken master resolution DRI.
• If the revert involves a database migration, please read through Deleting existing migrations.
• Add the appropriate labels before the MR is created. We can skip CI/CD jobs only if the labels are added before the CI/CD pipeline is created.

Milestone info

• I am reverting something in the current milestone. No changelog is needed, and I've added a ~"regression:*" label.
• I am reverting something in a different milestone. A changelog is needed, and I've removed the ~"regression:*" label.

Related issues and merge requests

Support Microsoft SAML attribute names by default (!135770 - merged)

#420766 (closed)