Update docs/modules/ROOT/pages/upgrade_to_version_2.adoc

Co-authored-by: Benjamin Quorning <[email protected]>

Author: pirj

docs/modules/ROOT/pages/upgrade_to_version_2.adoc

@@ -9,7 +9,7 @@ In version 2.x:
  - `CustomIncludeMethods` configuration option for `RSpec/EmptyExampleGroup` is removed
  - cop departments are nested for cops with a department that doesn’t match the extension name (`Capybara`, `FactoryBot`, `Rails`)
  - `AllCops/RSpec/Patterns`/`AllCops/FactoryBot/Patterns` options are removed
- - Calling `super` from `on_new_investigation` defined in a cop is mandatory now
+ - Calling `super` from `#on_new_investigation` defined in a cop is mandatory now
  - Avoid explicit definition of `cop` as `described_class.new`
 
 [discrete]