"eslint-plugin-testing-library@3.8.0" has incorrect peer dependency "eslint@^5 || ^6"

[nelsonni]

Describe the bug
Until testing-library/eslint-plugin-testing-library#139 is merged and released, yarn will continue to complain about a peer dependency version mismatch between eslint and eslint-plugin-testing-library:

warning " > eslint-plugin-testing-library@3.8.0" has incorrect peer dependency "eslint@^5 || ^6".

The version mismatch is caused by adherence to semantic versioning in Yarn's Dependency Versioning, in particular the Caret Ranges which means that eslint@^5 || ^6 translates to >=5.0.0 <7.0.0, and packages.json has the eslint package pegged at version ^7.3.0.

To Reproduce
Steps to reproduce the behavior:

1. Run yarn add eslint-plugin-testing-library
2. See error

Expected behavior
Per the discussions in testing-library/eslint-plugin-testing-library#139, there should be no difference in behavior after updating eslint-plugin-testing-library to include eslint@^5 || ^6 || ^7 in the peer dependencies except that yarn will stop displaying the warning.

Screenshots

Versions (please complete the following information):

• OS: MacOS, Windows, Linux
• Synectic Version: 1.0.0-beta (branch: development)

Additional context
The inclusion of eslint-plugin-testing-library is part of the effort to improve testing infrastructure using React Testing Library.