Drop DEP_SCAN_DISABLE_REMOTE_CHECKS flag variable support for Dependency Scanning jobs

Proposal

Remove DEP_SCAN_DISABLE_REMOTE_CHECKS flag variable support in Auto DevOps and vendored CI/CD job templates in %12.0.

Execution

• [X] Remove support from code of the Dependency Scanning project Done in %12.5
• [X] Remove support from Auto DevOps template No longer necessary since Auto-Devops now uses the vendored template.
• Remove support from vendored template for Dependency Scanning: !20982 (merged)
• [X] Remove mention of DEP_SCAN_DISABLE_REMOTE_CHECKS from README of the Dependency Scanning project Done in %12.5

Product

[ ] release post