* docs: clear up multiple-providers is unimplemented
Currently this configuration option is held up by #926. So users don't
assume this solution will work for them, and later find the feature is
not yet implemented -- own the shortcoming clearly.
* doc: add note about missing multi provider implementation to versioned docs
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Signed-off-by: Jan Larwig <jan@larwig.com>
Co-authored-by: Jan Larwig <jan@larwig.com>
