fix(lsphp): repair the comment my sed mangled

My previous commit used sed with | as both delimiter and literal, which
corrupted the comment line rather than changing -m to -i. The assertion
command itself was never touched and is correct.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Dockerfile.lsphp

@@ -87,7 +87,7 @@ RUN bash -c 'set -e; \
 ## cac_path_parity.from/.to mapping, so it is safe in any context (including
 ## wp-cli runs, where $_SERVER carries no filesystem paths).
 ##
- grep` is a BUILD-TIME ASSERTION| grep` is a BUILD-TIME ASSERTION: if the .so fails to
+## The trailing `lsphp -i | grep` is a BUILD-TIME ASSERTION: if the .so fails to
 ## load (ABI drift after a base-image PHP bump, bad build) the image build fails
 ## here rather than shipping a sidecar that silently lost path parity.
 ## NOTE: probe lsphp with `-i` ONLY. The lsphp binary is the LSAPI SAPI, not the