Skip executeFile001 in threaded2 way

As noted in ghc/ghc#16814, this test is remarkably fragile
when run concurrently.

tests/all.T

@@ -69,6 +69,6 @@ test('T3816', normal, compile_and_run, ['-package unix'])
 
 test('processGroup001', normal, compile_and_run, ['-package unix'])
 test('processGroup002', normal, compile_and_run, ['-package unix'])
-test('executeFile001', omit_ways(prof_ways), compile_and_run, ['-package unix'])
+test('executeFile001', omit_ways(prof_ways + ['threaded2']), compile_and_run, ['-package unix'])
 
 test('T8108', normal, compile_and_run, ['-package unix'])