Add changelog for 473
This MR was automatically created from CI, https://gitlab.com/gitlab-org/gitter/gitter-android-app/-/jobs/542552445
We moved CURRENT_VERSION.txt
-> 473.txt
This MR was automatically created from CI, https://gitlab.com/gitlab-org/gitter/gitter-android-app/-/jobs/542552445
We moved CURRENT_VERSION.txt
-> 473.txt