Fix unnecessary array in JSON schema
Fix unnecessary array in JSON schema

In the JSON schema we have definitions like `"type": ["object", "array"],` or `"type": "string",`.
The key `"minimum-stability"` has a `"type": ["string"],`.
The array definition with `[` and `]` is unnecessary here, because it can only contain a string.
ezsystems/satis,ezsystems/satis,gencer/satis,alcohol/satis,andkirby/satis,alcohol/satis,gencer/satis,andkirby/satis,alcohol/satis,andkirby/satis,composer/satis,gencer/satis,composer/satis,MoT3rror/satis,yonh/satis,ezsystems/satis,yonh/satis,composer/satis,MoT3rror/satis,alcohol/satis