TIKA-4703: Fix chmod failure in tika-grpc Dockerfile on CI

The chmod was running after USER $UID_GID, so it ran as the non-root user
and could not change permissions on the root-owned file copied from the
build context. This worked locally because the file already had the execute
bit set on the host filesystem, but CI builds start with a clean context
where the bit is absent.

Move chmod to before the USER switch so it runs as root.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: nddipiazza

tika-grpc/docker-build/Dockerfile

@@ -49,14 +49,15 @@ RUN set -eux \
     && apt-get clean -y \
     && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
+RUN chmod +x "/tika/bin/start-tika-grpc.sh"
+
 USER $UID_GID
 
 EXPOSE 9090
 ENV TIKA_VERSION=$VERSION
 ENV TIKA_GRPC_MAX_INBOUND_MESSAGE_SIZE=$TIKA_GRPC_MAX_INBOUND_MESSAGE_SIZE
 ENV TIKA_GRPC_MAX_OUTBOUND_MESSAGE_SIZE=$TIKA_GRPC_MAX_OUTBOUND_MESSAGE_SIZE
 ENV TIKA_GRPC_NUM_THREADS=$TIKA_GRPC_NUM_THREADS
-RUN chmod +x "/tika/bin/start-tika-grpc.sh"
 ENTRYPOINT ["/tika/bin/start-tika-grpc.sh"]
 
 LABEL maintainer="Apache Tika Developers dev@tika.apache.org"