Migrate java-event-logs-tags.py to python3.

These are used in the Bazel Android app builds.

Test: m droid
Test: CI
Test: b run //build/make/tools:java-event-log-tags

Change-Id: Iaffe6f974008d1a0532a849353d25df02197afd2
diff --git a/tools/BUILD.bazel b/tools/BUILD.bazel
index 75b0de6..3170820 100644
--- a/tools/BUILD.bazel
+++ b/tools/BUILD.bazel
@@ -8,7 +8,7 @@
     srcs=["java-event-log-tags.py"],
     deps=[":event_log_tags"],
     visibility = ["//visibility:public"],
-    python_version = "PY2",
+    python_version = "PY3",
 )
 
 py_binary(
@@ -16,5 +16,5 @@
     srcs=["merge-event-log-tags.py"],
     deps=[":event_log_tags"],
     visibility = ["//visibility:public"],
-    python_version = "PY2",
+    python_version = "PY3",
 )