GSL/docs/upgrade_checklist.md

When bumping the version, you need to update the following files:

1. CMakeLists.txt Bump GSL_VERSION
2. README.md Bump GIT_TAG
3. ios.yml Bump MACOSX_BUNDLE_BUNDLE_VERSION and MACOSX_BUNDLE_SHORT_VERSION_STRING

After updating, you need to create a new GitHub release:

1. Microsoft/GSL - Create Release

Be sure to update the release notes accordingly and properly mention open-source contributors.

After a new release exists, update the ms-gsl vcpkg port:

1. Microsoft/vcpkg - ms-gsl port

Be sure to monitor the PR that updates the port for any feedback from vcpkg maintainers.