Merge pull request #1222 from taus-semmle/python-unify-old-and-new-query-suites

Python: Make old query suites point to new query suites.

Author: markshannon

python/config/suites/lgtm/python2-alerts-lgtm

@@ -1,2 +1,4 @@
-@import "python2-queries-lgtm"
-@import "python2-metrics-lgtm"
+# This file (and the other python2- files in this directory) is present for
+# backwards compatibility, and can be removed once we reach version 1.23.
+
+@import "python-lgtm"