Move DSL namespace from supportLibrary to androidx.

Test: ./gradlew createArchive
Change-Id: I07a66c4685daec2b72c83a8fbff9430ec9764a64
diff --git a/dumb-tests/build.gradle b/dumb-tests/build.gradle
index f26410b..0a29cc5 100644
--- a/dumb-tests/build.gradle
+++ b/dumb-tests/build.gradle
@@ -32,7 +32,7 @@
 
 uploadArchives.enabled = false
 
-supportLibrary {
+androidx {
     name = "Dummy Project for test runner"
     publish = false
 }
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