Remove #onConfigurationChanged from CoreStartable

Classes can now bind into the ConfigurationListener Set in order to
be automatically registered for configuration changes:

    @Binds
    @IntoSet
    fun bindFoobar(impl: Foobar): ConfigurationListener

Flag: NA
Bug: 221043476
Test: atest SystemUITests
Change-Id: If21c44d27afbab0cbb8fa9918cdd9f7ef9b30835