Add standard set of labels for docs repos

[sypets]

see decision: https://decisions.typo3.org/t/proposal-labels-for-issues-on-github-typo3-documentation/522

There, we propose to defined a standard set of labels for (documentation) repos. Repos like the theme and this repo might have other specific labesl.

Implementation

• GitHub app Settings
• new: GitHub has launched a new setting for new repos (see "Repository labels" setting)

[sypets]

Issue older than 2 years. No high priority. No one is working on this.