fix: update docs (#79)

* add barecheck app token input

* use github application token

* build new version

* fix sinfle line text

* add input test

* impove input args coverage

* update images and add docs about uncovered lines

* comment one test

* revert

* add installation

* fix typo

Author: vitaliimelnychuk

README.md

@@ -4,6 +4,12 @@ GitHub Action that generates coverage reports
 
 ![code coverage report success](./docs/img/barecheck-comment-success.png)
 
+## Installation
+
+1. Install [Barecheck Application](https://github.com/apps/barecheck)
+2. Copy the token provided on the authorization confirmation page and [add it to your build environment](https://docs.github.com/en/actions/reference/environment-variables) as LHCI_GITHUB_APP_TOKEN
+3. Create Github Actions worrkflow from the [example](https://github.com/barecheck/code-coverage-action#workflow-example)
+
 ## Show annotations
 
 As a part of code coverage report action also enable an ability to show annotations along with changed lines to keep control what is covered with tests without interapting review process