Bypass deprecation lint warning (#45)

CI is failing because of a deprecation notice on
`cel.OptCheckStringFormat`, but the recommended alternative doesn't
appear to exist. I've filed google/cel-go#837
upstream to clarify, but for now tests are passing so I think we can
safely bypass this lint error.

I also filed #44 so
that we don't forget to migrate to whichever API is recommended and
remove this bypass.

internal/celext/lib.go

@@ -268,7 +268,7 @@ func (l lib) ProgramOptions() []cel.ProgramOption {
 	return []cel.ProgramOption{
 		cel.EvalOptions(
 			cel.OptOptimize,
-			cel.OptCheckStringFormat,
+			cel.OptCheckStringFormat, //nolint:staticcheck
 		),
 	}
 }