test: consolidate Go tests (#39962)

Consolidate all Go tests. Coverage is identical to before. Go tests are
around 5% faster while being 7% smaller. No non-test code is touched.

modules/commitstatus/commit_status_test.go

@@ -173,11 +173,6 @@ func TestCombine(t *testing.T) {
 			states:   CommitStatusStates{CommitStatusSuccess, CommitStatusError, CommitStatusFailure, CommitStatusWarning},
 			expected: CommitStatusFailure,
 		},
-		{
-			name:     "mixed states",
-			states:   CommitStatusStates{CommitStatusPending, CommitStatusSuccess, CommitStatusError, CommitStatusWarning},
-			expected: CommitStatusFailure,
-		},
 		{
 			name:     "mixed states with all success",
 			states:   CommitStatusStates{CommitStatusSuccess, CommitStatusSuccess, CommitStatusPending, CommitStatusWarning},