Restructure buildSrc libraries

Make public library a real library to make IJ happy.

Test: Gradle sync in studio, buildSrc/private/ now resolves
Bug: 202177757
Change-Id: I98242e4c3c398d3350b45570a2556a25bc8662bb
diff --git a/buildSrc/settings.gradle b/buildSrc/settings.gradle
index 3d32906..35d9960 100644
--- a/buildSrc/settings.gradle
+++ b/buildSrc/settings.gradle
@@ -17,6 +17,7 @@
 include ":jetpad-integration"
 include ":plugins"
 include ":private"
+include ":public"
 
 enableFeaturePreview("VERSION_CATALOGS")