Avoid parentheses around block expressions

[Morriar]

Avoid unnecessary parentheses when autocorrecting T.must calls whose argument is a block expression.

Before:

T.must(options.find { |option| option.title == "Standard" })

was autocorrected to:

(options.find { |option| option.title == "Standard" }).not_nil!

After:

options.find { |option| option.title == "Standard" }.not_nil!