Fix#31657.
According to the
[doc](https://docs.github.com/en/actions/writing-workflows/workflow-syntax-for-github-actions#onschedule)
of GitHub Actions, The timezone for cron should be UTC, not the local
timezone. And Gitea Actions doesn't have any reasons to change this, so
I think it's a bug.
However, Gitea Actions has extended the syntax, as it supports
descriptors like `@weekly` and `@every 5m`, and supports specifying the
timezone like `TZ=UTC 0 10 * * *`. So we can make it use UTC only when
the timezone is not specified, to be compatible with GitHub Actions, and
also respect the user's specified.
It does break the feature because the times to run tasks would be
changed, and it may confuse users. So I don't think we should backport
this.
## ⚠️ BREAKING ⚠️
If the server's local time zone is not UTC, a scheduled task would run
at a different time after upgrading Gitea to this version.
Replace #22751
1. only support the default branch in the repository setting.
2. autoload schedule data from the schedule table after starting the
service.
3. support specific syntax like `@yearly`, `@monthly`, `@weekly`,
`@daily`, `@hourly`
## How to use
See the [GitHub Actions
document](https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#schedule)
for getting more detailed information.
```yaml
on:
schedule:
- cron: '30 5 * * 1,3'
- cron: '30 5 * * 2,4'
jobs:
test_schedule:
runs-on: ubuntu-latest
steps:
- name: Not on Monday or Wednesday
if: github.event.schedule != '30 5 * * 1,3'
run: echo "This step will be skipped on Monday and Wednesday"
- name: Every time
run: echo "This step will always run"
```
Signed-off-by: Bo-Yi.Wu <appleboy.tw@gmail.com>
---------
Co-authored-by: Jason Song <i@wolfogre.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>