Remove unnecessary call to delete all rules to reduce concurrent test flakiness (#374)

If two instances of tests were running on the same account in parallel,
it's possible for delete all rules to collide with itself. We removed
this previously for most of the other tests, one case of it appears to
have been left in

Author: brandon-wada

test/unit/test_actions.py

@@ -7,7 +7,6 @@
 
 def test_create_action(gl_experimental: ExperimentalApi):
     # We first clear out any rules in case the account has any left over from a previous test
-    gl_experimental.delete_all_rules()
     name = f"Test {datetime.utcnow()}"
     det = gl_experimental.get_or_create_detector(name, "test_query")
     rule = gl_experimental.create_rule(det, f"test_rule_{name}", "EMAIL", "test@example.com")