Allow using lru_cahe on methods.

I don't care about memory leaks, it's a very short lived Lambda
function.

src/_dns.py

@@ -15,7 +15,7 @@ class CheckDNS(Check):  # pylint: disable=abstract-method
     _domain = "shore.co.il"
     _subdomains = [_domain, f"www.{_domain}"]
 
-    @lru_cache(3)
+    @lru_cache(3)  # noqa: B019
     def _get_resolvers(self):
         """Return a list of resolvers for each nameserver in the DNS zone."""
         default_resolver = dns.resolver.Resolver()