[clang] [Clang] Propagate 'SystemDrive' environment variable for unit tests (PR #90478)

[Krystian Stasiowski via cfe-commits]

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@@ -32,6 +32,8 @@
 
 if "HOME" in os.environ:
     config.environment["HOME"] = os.environ["HOME"]
+if "SystemDrive" in os.environ:
+    config.environment["SystemDrive"] = os.environ["SystemDrive"]
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sdkrystian wrote:

Sure

https://github.com/llvm/llvm-project/pull/90478