1. Add some "render-content" classes to "markup" elements when the
content is rendered
2. Use correct "markup" wrapper for "preview" (but not set that class on
the tab)
3. Remove incorrect "markup" class from LFS file view, because there is
no markup content
* "edit-diff" is also removed because it does nothing
5. Use "initPdfViewer" for PDF viewer
6. Remove incorrect "content" class from milestone markup
7. Init all ".markup" elements by new init framework
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Numerous small UI fixes:
- Fix double border in collaborator list
- Fix system notice table background
- Mute links in repo and org lists
- Downsize projects edit buttons
- Improve milestones and project list rendering
- Condense milestone list entry to a single line of "metas"
- Mute ".." button in repo files list