• Previous syntax broke the docs-build
• Better naming; include a static config to model the allowed values for the instance config in an enum-like way

Fixes: #3141

Please make sure to read the Contributing Guidelines:

https://github.com/neomjs/neo/blob/dev/CONTRIBUTING.md

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• Bugfix
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Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

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• When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)

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