install_sdp.sh: treat opt_perforce_sdp_backup.service start failure as a warning, not an error.
Reports of install_sdp.sh reporting an error at this step even though the
service actually works and the install is fully usable afterward -- this
happens near the very end of the process, so users get a scary-looking
error for something that isn't one. Downgraded to warnmsg (ErrorCount
untouched, so the run still reports SUCCESS with a warning noted and
exits 0) while leaving the timer enable/start steps as real errors, since
those are more consequential if they fail.
Agent: Claude Code, Model: Claude Sonnet 5 (claude-sonnet-5), operating as bot_Claude_Anthropic.