Use correct response code in push mirror creation response in v1_json.tmpl (#25476)

In the process of doing a bit of automation via the API, we've
discovered a _small_ issue in the Swagger definition. We tried to create
a push mirror for a repository, but our generated client raised an
exception due to an unexpected status code.

When looking at this function:

https://github.com/go-gitea/gitea/blob/3c7f5ed7b5bff347198cbb26492e6354ea42733b/routers/api/v1/repo/mirror.go#L236-L240

We see it defines `201 - Created` as response:

https://github.com/go-gitea/gitea/blob/3c7f5ed7b5bff347198cbb26492e6354ea42733b/routers/api/v1/repo/mirror.go#L260-L262

But it actually returns `200 - OK`:

https://github.com/go-gitea/gitea/blob/3c7f5ed7b5bff347198cbb26492e6354ea42733b/routers/api/v1/repo/mirror.go#L373

So I've just updated the Swagger definitions to match the code😀

---------

Co-authored-by: Giteabot <[email protected]>

Author: GeorgDangl

routers/api/v1/repo/mirror.go

@@ -258,7 +258,7 @@ func AddPushMirror(ctx *context.APIContext) {
 	//   schema:
 	//     "$ref": "#/definitions/CreatePushMirrorOption"
 	// responses:
-	//   "201":
+	//   "200":
 	//     "$ref": "#/responses/PushMirror"
 	//   "403":
 	//     "$ref": "#/responses/forbidden"