Disable xrefs/coro1 test on open source.

Summary: Clang 15 is needed for this test, and since we're currently on Clang 12 we disable it for now. This turns the CI green on open-source!

Reviewed By: donsbot

Differential Revision: D55852003

fbshipit-source-id: 82531db53bddf1d057f74681240d191d8c6f55ac

glean/lang/clang/tests/github/Glean/Clang/Regression.hs

@@ -23,6 +23,7 @@ main = getArgs >>= \args ->
     expectedFailures = map ("--omit="++)
       [ "declarations/typeAlias1"
       , "declarations/objc-property1"
-      , "xrefs/using-directive4"
+      , "xrefs/coro1"             -- Needs Clang 15
+      , "xrefs/using-directive4"  -- Needs Clang 15
       , "index_failure/cpp"
       ]