[clang] [clang-format] Fix a regression in dumping the config (PR #80628)

[Ben Hamilton via cfe-commits]

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@@ -0,0 +1,3 @@
+// RUN: clang-format -dump-config 2>&1 | FileCheck %s
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bhamiltoncx wrote:

Can you also add a test with `clang-format --assume-filename=foo.m -dump-config 2>&1 | FileCheck %s`?

It should result in `Language: ObjC`.


https://github.com/llvm/llvm-project/pull/80628