Closes#1095.
`tea issues create` and `tea pulls create` now resolve the description in the same way as comments: when stdin is piped and neither `--description` nor `--description-file` is given, the body is read from stdin. Both create and edit commands also accept:
```text
--description-file <path> # '-' reads stdin
```
This avoids the PowerShell 5.1 argument mangling and ANSI code page issues described in #1095.
## Changes
- Add `--description-file` to `issues create`, `issues edit`, `pulls create`, and `pulls edit`.
- Create commands fall back to piped stdin when no description flag is set.
- Add unit tests for the new body resolution.
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Co-authored-by: bircni <bircni@icloud.com>
Reviewed-on: https://gitea.com/gitea/tea/pulls/1096
Reviewed-by: bircni <bircni@icloud.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Lunny Xiao