zinc: disable spurious failing test

Author: SethTisue

configs/community.dbuild

@@ -2122,8 +2122,10 @@ build += {
       "set executeTests in zincIvyIntegration in Test := Tests.Output(TestResult.Passed, Map(), Iterable())"
       // many failed tests with "sbt.internal.inc.InvalidComponent: The Scala compiler and library could not be retrieved"
       "set executeTests in zinc in Test := Tests.Output(TestResult.Passed, Map(), Iterable())"
-      // started failing in 2.12.9 nightlies
-      """set compilerBridgeTest/Test/unmanagedSources/excludeFilter := HiddenFileFilter || "ExtractUsedNamesPerformanceSpecification.scala""""
+      // ExtractUsedNmesPerformanceSpecification started failing in 2.12.9 nightlies
+      // ExtractUsedNamesSpecification is a silly spurious failure, as per
+      //   https://github.com/scala/scala-dev/issues/644#issuecomment-520540296
+      """set compilerBridgeTest/Test/unmanagedSources/excludeFilter := HiddenFileFilter || "ExtractUsedNamesPerformanceSpecification.scala" || "ExtractUsedNamesSpecification.scala""""
     ]
     deps.ignore: ["com.geirsson#scalafmt-core", "com.lucidchart#scalafmt-impl"]
     check-missing: false  // ignore missing scalafmt