[RELEASE ONLY CHANGES] Use prebuilt torch in MacOS CI jobs

Author: GregoryComer

.ci/scripts/utils.sh

@@ -107,7 +107,7 @@ install_pytorch_and_domains() {
   TORCHVISION_VERSION=$(cat .github/ci_commit_pins/vision.txt)
   export TORCHVISION_VERSION
 
-  install_domains
+  #install_domains
 
   popd || return
   # Print sccache stats for debugging

CMakeLists.txt

@@ -877,6 +877,11 @@ if(EXECUTORCH_BUILD_PYBIND)
       portable_lib PROPERTIES BUILD_RPATH "@loader_path/../../../torch/lib"
                               INSTALL_RPATH "@loader_path/../../../torch/lib"
     )
+    if(CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang"
+       and CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL "16.0"
+    )
+      target_link_options(portable_lib PRIVATE -Wl,-ldclassic)
+    endif()
   else()
     set_target_properties(
       portable_lib PROPERTIES BUILD_RPATH "$ORIGIN/../../../torch/lib"