Proposal: Add branch protection rules for o3de/community

[lmbr-pip]

Request to add branch protection rules:

• All contributions should be signed using standard DCO rules
• All contributions require 2 approvals

Seems that o3de/community does not have same standards as other branches

[lmbr-pip]

DCO is active in branch, but any "admin" can submit changes without approval. Should follow standard 2 person approval process as with any other PR for o3de