Extend presubmit to covert test and request (#1846)

Fix the casing *and* fix use of context as we were still referencing
the non-std lib context - no wondering how this could have worked...

test/file_test.go

@@ -6,7 +6,7 @@ func TestTempFile(t *testing.T) {
 	t.Parallel()
 	_, f, e := TempFile(".", "test")
 	if e != nil {
-		t.Fatalf("failed to create temp file: %s", e)
+		t.Fatalf("Failed to create temp file: %s", e)
 	}
 	defer f()
 }