migrate some more "OptionalBool" to "Option[bool]" (#29479)

just some refactoring bits towards replacing **util.OptionalBool** with
**optional.Option[bool]**

---------

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>

routers/web/user/search.go

@@ -8,7 +8,6 @@ import (
 
 	"code.gitea.io/gitea/models/db"
 	user_model "code.gitea.io/gitea/models/user"
-	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/services/context"
 	"code.gitea.io/gitea/services/convert"
 )
@@ -25,7 +24,7 @@ func Search(ctx *context.Context) {
 		Keyword:     ctx.FormTrim("q"),
 		UID:         ctx.FormInt64("uid"),
 		Type:        user_model.UserTypeIndividual,
-		IsActive:    util.OptionalBoolFromGeneric(ctx.FormOptionalBool("active")),
+		IsActive:    ctx.FormOptionalBool("active"),
 		ListOptions: listOptions,
 	})
 	if err != nil {