drop python2 testing entirely

No point in linting or testing when the code forces Python 3.6+.

Bug: None
Test: `repo upload` still works
Change-Id: I5af19b5dc70be3f5be99157d1fc4287e4437c553
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index 03350c7..81f505d 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg
@@ -1,21 +1,14 @@
 [Hook Scripts]
 # Only list fast unittests here.
-py2_config_unittest = python2 ./rh/config_unittest.py
-py3_config_unittest = python3 ./rh/config_unittest.py
-py2_hooks_unittest  = python2 ./rh/hooks_unittest.py
-py3_hooks_unittest  = python3 ./rh/hooks_unittest.py
-py2_shell_unittest  = python2 ./rh/shell_unittest.py
-py3_shell_unittest  = python3 ./rh/shell_unittest.py
-py2_utils_unittest  = python2 ./rh/utils_unittest.py
-py3_utils_unittest  = python3 ./rh/utils_unittest.py
-py2_android_test_mapping_format_unittest = python2 ./tools/android_test_mapping_format_unittest.py
-py3_android_test_mapping_format_unittest = python3 ./tools/android_test_mapping_format_unittest.py
-py2_config_test = python2 ./rh/config_test.py --check-env --commit-id ${PREUPLOAD_COMMIT} --commit-msg ${PREUPLOAD_COMMIT_MESSAGE} --repo-root ${REPO_ROOT} -- ${PREUPLOAD_FILES}
-py3_config_test = python3 ./rh/config_test.py --check-env --commit-id ${PREUPLOAD_COMMIT} --commit-msg ${PREUPLOAD_COMMIT_MESSAGE} --repo-root ${REPO_ROOT} -- ${PREUPLOAD_FILES}
+config_unittest = ./rh/config_unittest.py
+hooks_unittest  = ./rh/hooks_unittest.py
+shell_unittest  = ./rh/shell_unittest.py
+utils_unittest  = ./rh/utils_unittest.py
+android_test_mapping_format_unittest = ./tools/android_test_mapping_format_unittest.py
+config_test = ./rh/config_test.py --check-env --commit-id ${PREUPLOAD_COMMIT} --commit-msg ${PREUPLOAD_COMMIT_MESSAGE} --repo-root ${REPO_ROOT} -- ${PREUPLOAD_FILES}
 
 [Builtin Hooks]
 commit_msg_bug_field = true
 commit_msg_changeid_field = true
 commit_msg_test_field = true
-pylint2 = true
 pylint3 = true