[csharp] Fixed any of inline enum

[devhl-labs]

Fixes #21585 just ensure to use this in the config:

inlineSchemaOptions:
RESOLVE_INLINE_ENUMS: true

The existing samples receive a spacing and casing fix. The new sample shows that an any of with an inline enum works. I had to use a new sample because not including the inline schema option means it no longer compiles.

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