Paper: Bring option to enable protection stacking

[samolego]

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is.
It's the feature request from previous version of MC (1.14 - 1.14.2)

Describe the solution you'd like
A boolean in paper config to allow protection stacking, aka creating "god armor". For example, being able to put "fire protection" on chestplate already enchanted with "protection".

[aeonlamb]

I don't see the point to re-introducing an obvious bug. Also, seems like something a plugin could easily do.

[zachbr]

Also, seems like something a plugin could easily do