Modified the PR template to include a mention that the README.md file should be updated if necessary

Author: bgorski

.github/PULL_REQUEST_TEMPLATE.md

@@ -43,4 +43,5 @@
  - [ ] Pull request has a meaningful description of its purpose
  - [ ] All commits are accompanied by meaningful commit messages
  - [ ] All new or changed code is covered with unit/integration tests (if applicable)
+ - [ ] README.md files for modified modules are updated and included in the pull request if [README.md predefined sections](https://github.com/magento/devdocs/wiki/Magento-module-README.md) require an update
  - [ ] All automated tests passed successfully (all builds are green)