Add rootProject.name to decouple the AS name from the directory

By default Android Studio will name the project based on the root
directory it's opened from. This gives a consistent (and clear) name
regardless of what root directory the project is located in on the
filesystem.

Explicitly defining `rootProject.name` is recommended here:
https://docs.gradle.org/current/userguide/multi_project_builds.html#naming_recommendations

PiperOrigin-RevId: 528729078

settings.gradle

@@ -18,7 +18,7 @@ if (gradle.ext.has('androidxMediaModulePrefix')) {
     modulePrefix += gradle.ext.androidxMediaModulePrefix
 }
 
-rootProject.name = 'media3'
+rootProject.name = 'androidx.media3'
 
 include modulePrefix + 'demo'
 project(modulePrefix + 'demo').projectDir = new File(rootDir, 'demos/main')