net/url: fail TestParseErrors test when getting an unwanted error

The TestParseErrors test function was not strict with unwanted errors
received from url.Parse(). It was not failing in such cases, now it does.

Updates golang#33646 and golang#29098

src/net/url/url_test.go

@@ -1456,7 +1456,7 @@ func TestParseErrors(t *testing.T) {
 			continue
 		}
 		if err != nil {
-			t.Logf("Parse(%q) = %v; want no error", tt.in, err)
+			t.Errorf("Parse(%q) = %v; want no error", tt.in, err)
 		}
 	}
 }