* Revert "MM-54502 - Update regex to force first character to be alpha (#24675)"
This reverts commit 08ed72f060.
* update tests for reverted PR
* Revert "update tests for reverted PR"
This reverts commit c1cf5495fa129008e44a8fcdc0ee34762b33dd34.
* Revert "Revert "MM-54502 - Update regex to force first character to be alpha (#24675)""
This reverts commit 6920b979c8dba86a837bafff7c057dc609c6aa58.
* only revert important parts, not tests
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