OIDC ENABLE_OAUTH_SIGNUP

[wm-ek]

Docs say "ENABLE_OAUTH_SIGNUP" is persistent.

However, i checked the database. This variable is not stored (yet?).

Also, it is possible to change it in the compose file and after a reload the new value is set/loaded.

For us personally this is good, because we need it that way. but docs shouldn't say its persistent.