Remove git metadata copy - test if webpack works without it

Webpack might use JELLYFIN_VERSION env var as fallback

docker/Dockerfile

@@ -63,8 +63,6 @@ RUN apk add \
  && git config --global --add safe.directory /jellyfin/jellyfin-web
 
 WORKDIR ${SOURCE_DIR}
-# Copy submodule git metadata to parent directory where jellyfin-web/.git references it
-COPY .git/modules/jellyfin-web /.git/modules/jellyfin-web
 COPY jellyfin-web .
 
 RUN npm ci --no-audit --unsafe-perm \