[llvm] Attempt to use composite action for libc++ builders. (PR #74489)

[Tom Stellard via llvm-commits]

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@@ -0,0 +1,44 @@
+name: 'Run Buildbot for libc++'
+description: 'Invoke the run-buildbot script with the specified parameters'
+
+inputs:
+  configuration:
+    description: 'the configuration to build'
+    required: true
+  cxx:
+    description: 'C++ compiler'
+    required: true
+  cc:
+    description: 'C compiler'
+    required: true
+  enable_clang_tidy:
+    description: 'enable clang-tidy'
+    required: false
+    default: 'OFF'
+  enable_std_modules:
+    description: 'enable std modules'
+    required: false
+    default: 'OFF'
+
+runs:
+  using: "composite"
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tstellar wrote:

What does this do?

https://github.com/llvm/llvm-project/pull/74489