Add types for rubocop ast

[kozy4324]

Add types to:

• rubocop-ast
  • RuboCop::AST::PairNode
  • RuboCop::AST::RegexpNode
  • RuboCop::AST::SendNode
  • RuboCop::AST::StrNode

[github-actions]

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rubocop-ast

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[kozy4324]

/merge