[BUG][DOCS] Documentation references deprecated adoptopenjdk/openjdk Homebrew tap

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

README.md install instructions for Homebrew reference the adoptopenjdk/openjdk tap:

https://github.com/OpenAPITools/openapi-generator/blob/bdad11d0270f0b3a0ee75352820626b2e3958e3e/README.md?plain=1#L304-L309

This repository has not been updated since 2021, and is broken on the current version of Homebrew:

Error: Unexpected method 'appcast' called on Cask adoptopenjdk-jre.
Follow the instructions here:
  https://github.com/Homebrew/homebrew-cask#reporting-bugs
Error: Unexpected method 'appcast' called on Cask adoptopenjdk-openj9.
Follow the instructions here:
  https://github.com/Homebrew/homebrew-cask#reporting-bugs
Error: Unexpected method 'appcast' called on Cask adoptopenjdk-openj9-jre.
Follow the instructions here:
  https://github.com/Homebrew/homebrew-cask#reporting-bugs
Error: Unexpected method 'appcast' called on Cask adoptopenjdk-openj9-jre-large.
Follow the instructions here:
  https://github.com/Homebrew/homebrew-cask#reporting-bugs
Error: Calling `caveats :discontinued` is disabled! Use `deprecate!` instead.

The current version of the openapi-generator Homebrew recipe points at openjdk@11 in the main Homebrew repository, so there is no need to install it manually from an external source.

openapi-generator version

Documentation issue, present at commit 25b6fd3937aae49f28e3c924b22def766251762b

OpenAPI declaration file content or url

n/a

Generation Details

n/a

Steps to reproduce

https://github.com/OpenAPITools/openapi-generator/blob/bdad11d0270f0b3a0ee75352820626b2e3958e3e/README.md?plain=1#L306-L308

Related issues/PRs

None

Suggest a fix

Suggest installing OpenJDK with the openjdk@11 package, rather than from the AdoptOpenJDK/openjdk Homebrew tap.

Start in README.md at the Homebrew installation instructions linked in the issue and compare them with the current openapi-generator Homebrew recipe. Update the instructions to use the openjdk@11 package instead of the deprecated AdoptOpenJDK tap, then verify that the documented commands match the current Homebrew setup.