label are not rendered in wiki only project
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### Summary
Labels are not rendered in wikis when issue **and** repository permissions are disabled on project
### Steps to reproduce
Disable issue **and** repository permissions on project settings

### Example Project
https://gitlab.com/ezzarghili/label-wiki/wikis/home
### What is the current *bug* behavior?
instead of rendering the colored label the actual text is shown so gitlab-ce~2278648 will display `~bug`
### What is the expected *correct* behavior?
The actual label should be rendered properly
### Relevant logs and/or screenshots
Wiki page text
```markdown
this is the label ~MyLabel
```
**Expected:**

**Current:**

### Output of checks
This bug happens on GitLab.com
Also happens on a local on-premise version of gitlab
#### Results of GitLab environment info
#### Results of GitLab application Check
### Possible fixes
issue