[Fix #9955] Fix Style/ExplicitBlockArgument adding a second set of parentheses

[dvandersluis]

When Style/ExplicitBlockArgument adds the block argument to a def or send node, if the node already had empty parentheses after it, the corrector would add a second set, ie:

def my_method()
  foo { yield }
end

would become

def my_method(&block)()
  foo(&block)
end

In the original issue, once all these corrections (plus from Lint/UnusedMethodArgument and Style/DefWithParentheses) were resolved, the method would end up without a block argument.

Fixes #9955.

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[bbatsov]

Someone's on a hot PR streak! 😆 🚀