-releng: remove #browser-tests, fix -infra
-releng: remove #browser-tests, fix -infra

* Removed #browser-tests as that is a tag for anyone to use about their
  browser tests. It is not a project "owned" by Release Engineering.

* Fixed the capitalization of #browser-tests-infrastructure, because.

Change-Id: I278ee43bf6465cc27b28081456dd49296461c105

wikimedia/labs-tools-wikibugs2,wikimedia/labs-tools-wikibugs2