fix: allow configmap and secret references in the apiServer.env field

[LucasRoesler]

The Helm schema validation for apiServer.env should allow specifying static values, values from ConfigMaps, and values from Secrets, the same as all of the other services.

Update the values.schema.json so that the apiServer.env schema matches the schema from the other services, e.g. the schema for webserver.

Closes #51190

[boring-cyborg]

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[romsharon98]

static checks fail

[romsharon98]

@LucasRoesler Congrats on your first PR 🥳