The port vendors node_modules at fetch time (pre-fetch), so the "npm ci"
step would fail without network access.  Only run the actual web UI build.

--- cmake/targets/common.cmake.orig
+++ cmake/targets/common.cmake
@@ -54,8 +54,7 @@
 
 add_custom_target(web-ui ALL
         WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
-        COMMENT "Installing NPM Dependencies and Building the Web UI"
-        COMMAND "$<$<BOOL:${WIN32}>:cmd;/C>" "${NPM}" ci ${NPM_INSTALL_FLAGS}
-        COMMAND "${CMAKE_COMMAND}" -E env "SUNSHINE_BUILD_HOMEBREW=${NPM_BUILD_HOMEBREW}" "SUNSHINE_SOURCE_ASSETS_DIR=${NPM_SOURCE_ASSETS_DIR}" "SUNSHINE_ASSETS_DIR=${NPM_ASSETS_DIR}" "$<$<BOOL:${WIN32}>:cmd;/C>" "${NPM}" run build  # cmake-lint: disable=C0301
+        COMMENT "Building the Web UI (npm dependencies are vendored by the port)"
+        COMMAND "${CMAKE_COMMAND}" -E env "SUNSHINE_BUILD_HOMEBREW=${NPM_BUILD_HOMEBREW}" "SUNSHINE_SOURCE_ASSETS_DIR=${NPM_SOURCE_ASSETS_DIR}" "SUNSHINE_ASSETS_DIR=${NPM_ASSETS_DIR}" "$<$<BOOL:${WIN32}>:cmd;/C>" "${NPM}" run build  # cmake-lint: disable=C0301
         COMMAND_EXPAND_LISTS
         VERBATIM)