fix: exclude me-south-1 and sa-east-1 from E2E tests

These regions have infrastructure issues causing consistent E2E
test failures. Excluding them from the test region pool to reduce
noise and improve signal-to-noise ratio in E2E results.

Regions excluded:
- me-south-1 (BAH) - broken RDS infrastructure
- sa-east-1 - consistent test failures

Note: me-central-1 (DXB) was not present in the release branch
region pool so no change needed for it.

Author: sarayev