更轻量的基于 alpine 的 Dockerfile

[wy580477]

基于 Alpine 的 Dockerfile，构建以后 image 只有 210MB。

出于轻量化考虑，没有包括 ffmpeg 和 tesseract-ocr，需要的用户可以用 docker exec <容器名> apk add ffmpeg 的方式自行安装。

Description

Please carefully read the Contributing note and Code of conduct before making any pull requests. And, Do not make a pull request to merge into master unless it is a hotfix. Use the development branch instead.

Issues fixed by this PR

Type of changes

• [ ] Bug fix
• [ ] New feature
• [x] Enhancement
• [ ] Documentation

Checklist:

• [x] My code follows the style guidelines of this project
• [x] My pull request is unique and no other pull requests have been opened for these changes
• [x] I have read the Contributing note and Code of conduct
• [x] I am responsible for any copyright issues with my code if it occurs in the future.

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[omg-xtao]

Merged, thanks.

[wy580477]

Merged, thanks.

我又想了想，python 是不是固定版本比较好，固定到开发环境的版本，避免 python 版本不一样可能出问题。