Revert "Update minimum supported targetSdk to 29"

Revert "Expect warning message for app targetSdk < 29"

Revert submission 19380683-increase-min-target-sdk-version

Reason for revert: Test failures
Reverted Changes:
Ie4a4ad6d4:Update minimum supported targetSdk to 29
Icda326d6e:Expect warning message for app targetSdk < 29

Change-Id: I46c71b21e97d702408ecca8c8c0172e5f92ceb0c
diff --git a/core/version_util.mk b/core/version_util.mk
index 1c8574c..cbfef96 100644
--- a/core/version_util.mk
+++ b/core/version_util.mk
@@ -251,6 +251,6 @@
   # Used to set minimum supported target sdk version. Apps targeting sdk
   # version lower than the set value will result in a warning being shown
   # when any activity from the app is started.
-  PLATFORM_MIN_SUPPORTED_TARGET_SDK_VERSION := 29
+  PLATFORM_MIN_SUPPORTED_TARGET_SDK_VERSION := 23
 endif
 .KATI_READONLY := PLATFORM_MIN_SUPPORTED_TARGET_SDK_VERSION