Fix: Fix false negative for `RSpec/Dialect` when specified Capybara-specific methods

[sanfrecce-osaka]

fixed https://github.com/rubocop/rubocop-rspec/issues/1951

RuboCop::Cop::RSpec::Dialect#rspec_method? detects if node's second child is an RSpec block using RuboCop::RSpec::Language::ALL.all. However, RuboCop::Cop::RSpec::Dialect#rspec_method? returned nil because the following Capybara-specific methods were not set in config/default.yml.

• given
• given!
• background

I remove the line that checks if it’s a rspec_method? and add a inside_example_group? check.

cf. https://github.com/rubocop/rubocop-rspec/issues/1951#issuecomment-2296916136

Due to the above, it wouldn't filter out are calls with an explicit receiver where the receiver is not RSpec, eg foo.describe. so the following examples were removed.

• allows calling methods named xxx in examples

---

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• [x] Feature branch is up-to-date with master (if not - rebase it).
• [x] Squashed related commits together.
• [x] Added tests.
• [ ] Updated documentation.
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