Fix activity type match in `matchPullRequestEvent` (#25746)

Fix activity type match in `matchPullRequestEvent` (#25746)

Fix #25736
Caused by #24048

Right now we only check the activity type for `pull_request` event when
`types` is specified or there are no `types` and filter. If a workflow
only specifies filters but no `types` like this:
```
on:
  pull_request:
    branches: [main]
```
the workflow will be triggered even if the activity type is not one of
`[opened, reopened, sync]`. We need to check the activity type in this
case.

Co-authored-by: Giteabot <teabot@gitea.io>