[clang] [llvm] Disable compiling and testing Flang on Clang changes (PR #92740)

[Mehdi Amini via llvm-commits]

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@@ -68,7 +68,7 @@ function compute-projects-to-test() {
       done
     ;;
     clang)
-      for p in clang-tools-extra compiler-rt flang lldb cross-project-tests; do
+      for p in clang-tools-extra compiler-rt lldb cross-project-tests; do
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joker-eph wrote:

To not forget how we got to this PR: https://discourse.llvm.org/t/flang-tests-are-extremely-slow-on-windows/78591

Which is 1) Flang only and 2) Windows specific. Pasting what I wrote there:

> MLIR tests ran in 13.13s on Linux and 34.81s on Windows, so 2.65x slower.
> Flang tests ran in 5.98s on Linux and 1220.35s on Windows, so >200x slower.


https://github.com/llvm/llvm-project/pull/92740