DO NOT MERGE: Reintroduce BRIDGE_NOT_AVAILABLE bug for testing!

Revert "Revert "CA-98090: Block SXM when VM cannot match any bridge names on destination""

This reverts commit 190754336a907c173f6a4facb81a2e494d47dd1a.
Provide private workaround scripts for sctx-1928

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>