Answer
Rather than trying to suppress the check, add the missing method implementation — this P2 SCA warning specifically means the action's corresponding method implementation is missing from the .plsvc file; even some core IFS entity actions intentionally have a placeholder without a full implementation, which is why you can see the same warning in unmodified core files. Adding a minimal method skeleton for the action in your .plsvc file (implementing it, even minimally, rather than leaving it as a declared-but-unimplemented action) is what resolves the SCA error and unblocks deployment.