prop(docs): Remove early development hint from chips

The docs of the chip component still contains a early development hint, is this still needed? A lot of features have been released since the notice was added and it may send out wrong signals.

Note: chips are still early in their development and more features are being actively worked on.

If not, I can take care of it.

[jelbourn]

Yeah, that should be removed. PRs welcome.

Closed via #9818

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