Roll a release (2.11.0)

[SethTisue]

• fix and merge Add implementation of distinctBy #602
• tag: https://github.com/scala/scala-collection-compat/releases/tag/v2.11.0
• release job: https://github.com/scala/scala-collection-compat/actions/runs/5284080018
• sample artifact on Maven Central: https://repo1.maven.org/maven2/org/scala-lang/modules/scala-collection-compat_3/2.11.0/scala-collection-compat_3-2.11.0.jar
• adjust version policy intention, post-release: reset version policy, post-2.11.0 #605