Deprecate query string auth tokens (#28390)

## Changes
- Add deprecation warning to `Token` and `AccessToken` authentication
methods in swagger.
- Add deprecation warning header to API response. Example: 
  ```
  HTTP/1.1 200 OK
  ...
  Warning: token and access_token API authentication is deprecated
  ...
  ```
- Add setting `DISABLE_QUERY_AUTH_TOKEN` to reject query string auth
tokens entirely. Default is `false`

## Next steps
- `DISABLE_QUERY_AUTH_TOKEN` should be true in a subsequent release and
the methods should be removed in swagger
- `DISABLE_QUERY_AUTH_TOKEN` should be removed and the implementation of
the auth methods in question should be removed

## Open questions
- Should there be further changes to the swagger documentation?
Deprecation is not yet supported for security definitions (coming in
[OpenAPI Spec version
3.2.0](https://github.com/OAI/OpenAPI-Specification/issues/2506))
- Should the API router logger sanitize urls that use `token` or
`access_token`? (This is obviously an insufficient solution on its own)

---------

Co-authored-by: delvh <dev.lh@web.de>

templates/swagger/v1_json.tmpl

@@ -24046,6 +24046,7 @@
   },
   "securityDefinitions": {
     "AccessToken": {
+      "description": "This authentication option is deprecated for removal in Gitea 1.23. Please use AuthorizationHeaderToken instead.",
       "type": "apiKey",
       "name": "access_token",
       "in": "query"
@@ -24078,6 +24079,7 @@
       "in": "header"
     },
     "Token": {
+      "description": "This authentication option is deprecated for removal in Gitea 1.23. Please use AuthorizationHeaderToken instead.",
       "type": "apiKey",
       "name": "token",
       "in": "query"