Fail the Docker build when pip check fails

Docker's shell-form RUN only propagates the last command's exit status,
so once pip check moved ahead of the SDK_VERSION block its failure was
silently discarded whenever SDK_VERSION was empty or the override
install succeeded. Gate it explicitly with || exit 1.

Addresses PR#289 review finding.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Signed-off-by: lelia <2418071+lelia@users.noreply.github.com>

Author: lelia

Dockerfile

@@ -143,7 +143,7 @@ RUN if [ "$USE_LOCAL_INSTALL" = "true" ]; then \
             echo "Failed to install socketsecurity==$CLI_VERSION after 10 attempts"; \
             exit 1; \
         fi; \
-        pip check; \
+        pip check || exit 1; \
         if [ ! -z "$SDK_VERSION" ]; then \
             pip install --index-url ${PIP_INDEX_URL} --extra-index-url ${PIP_EXTRA_INDEX_URL} socketdev==${SDK_VERSION}; \
         fi; \