Fix: Remove take check from Style/UnpackFirst cop

[parkerfinch]

Enumerable#take returns an Array, so the "bad" example
'foo'.unpack('h*').take(1) returns a single element Array while
the "good" example 'foo'.unpack1('h*') returns a String.

Removing take from the methods checked by this cop prevents erroneous messages/autocorrects.

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• Added tests.
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[bdewater]

🤦‍♂️

Thanks!

[bbatsov]

The changes look good, but your branch has to be rebased on top of the current master branch due to merge conflicts.

[parkerfinch]

Thanks @bbatsov, rebased!

[bbatsov]

Thanks!