[llvm] [Flang-RT][Offload] Always use LLVM-built GTest (PR #143682)

[David Spickett via llvm-commits]

================
@@ -392,6 +392,8 @@ function(llvm_ExternalProject_Add name source_dir)
                ${verbose}
                -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
                ${sysroot_arg}
+               -DCMAKE_C_COMPILER_LAUNCHER=ccache
+               -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
----------------
DavidSpickett wrote:

Testing change leftover?

https://github.com/llvm/llvm-project/pull/143682