Avoid creating IsFileOfInterest keys for non workspace files

Author: pepeiborra

ghcide/src/Development/IDE/Core/FileStore.hs

@@ -129,7 +129,8 @@ getModificationTimeImpl vfs isWatched missingFileDiags file = do
         mbVirtual <- liftIO $ getVirtualFile vfs $ filePathToUri' file
         -- we use 'getVirtualFile' to discriminate FOIs so make that
         -- dependency explicit by using the IsFileOfInterest rule
-        _ <- use_ IsFileOfInterest file
+        isWF <- isWorkspaceFile file
+        when isWF $ void $ use_ IsFileOfInterest file
         case mbVirtual of
             Just (virtualFileVersion -> ver) -> do
                 alwaysRerun