[SELC-5425] feat: Refactor API Group Support Policies with Common Policy

[manuraf]

List of Changes

• Common Policy Creation: A new common policy has been created that defines the MS_BACKEND_URL variable. This change simplifies the management of environment variables across different microservices within the Support group.
• Policy Removal: The old policies have been removed. These were identical in logic but differed only in the name of the policy and the environment variable specific to each microservice. Consolidating these into a single policy removes redundancy and reduces maintenance overhead.

Motivation and Context

This pull request refactors the policies within the Support API group by introducing a common policy that sets the MS_BACKEND_URL variable.

How Has This Been Tested?

Screenshots (if appropriate):

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.