testdata: update testdata git submodule to latest commit (for LLVM 14.0)

mewmew · mewmew · commit 8d86a1d00464 · 2022-08-02T06:46:41.000+02:00
diff --git a/testdata b/testdata
@@ -1 +1 @@
-Subproject commit 4afe0cd0ac1989892254a24081e3b90adf63ed79
+Subproject commit 67c813281c22f4181af9d917e6f0a9e3a4334dfb
