Update minimum supported targetSdk to 29

Trailing by 4 major releases, as per schedule.

Test: make

Bug: 215522897
Change-Id: I33cd75a1092cb54f3f56bab6083d8f9211a32b64
diff --git a/core/version_util.mk b/core/version_util.mk
index cbfef96..00174d9 100644
--- a/core/version_util.mk
+++ b/core/version_util.mk
@@ -170,7 +170,7 @@
   # to the public SDK where platform essentially supports all previous SDK versions,
   # platform supports only a few number of recent system SDK versions as some of
   # old system APIs are gradually deprecated, removed and then deleted.
-  PLATFORM_SYSTEMSDK_MIN_VERSION := 28
+  PLATFORM_SYSTEMSDK_MIN_VERSION := 29
 endif
 .KATI_READONLY := PLATFORM_SYSTEMSDK_MIN_VERSION