The command order of prepare-docs is incorrect.
We should prepare same version with different locale at once, otherwise the doc files for `zh-cn` in `i18n` folder will be incorrect.
Before: (files in current is as same as version 1.19)

After:

Co-authored-by: Lunny Xiao <[email protected]>
Reviewed-on: https://gitea.com/gitea/gitea-docusaurus/pulls/92
Reviewed-by: Lunny Xiao <[email protected]>
Reviewed-by: silverwind <[email protected]>
Co-authored-by: yp05327 <[email protected]>
Co-committed-by: yp05327 <[email protected]>
Close#28287
## How to test it in local
convert Makefile L34 into:
```
cd .tmp/upstream-docs && git clean -f && git reset --hard && git fetch origin pull/28302/head:pr28302 && git switch pr28302
```
https://gitea.com/gitea/gitea-docusaurus/actions/runs/661/jobs/0#jobstep-9-39
I noticed that there are many warning logs in building docs.
It is causing 404 in docs.gitea.com now, so we need to fix it.
And there are also some other problems in v1.19 which can not be done in
this PR.
ps: Are there any good methods to test this in local?
Follow #28191
There are some misadded docs in #24914's backport PR #25016.
The following package registries are all supported in 1.20, so we should
not have docs in v1.19
- Alpine (#23714)
- CRAN (#22343)
- Debain (#24426)
- Go (#24687)
- RPM (#23380)