Enable readability-container-size-empty tests

This one is a little trivial, but it does help in readability.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I5366d4eec8af2f781b3bad804131ae2eb806e3aa
diff --git a/redfish-core/lib/redfish_util.hpp b/redfish-core/lib/redfish_util.hpp
index 881bf1a..a51aafd 100644
--- a/redfish-core/lib/redfish_util.hpp
+++ b/redfish-core/lib/redfish_util.hpp
@@ -62,7 +62,7 @@
                 BMCWEB_LOG_ERROR << ec;
                 return;
             }
-            if (subtree.size() == 0)
+            if (subtree.empty())
             {
                 BMCWEB_LOG_DEBUG << "Can't find chassis!";
                 return;
@@ -183,7 +183,7 @@
                 callback(ec, 0);
                 return;
             }
-            if (resp.size() < 1)
+            if (resp.empty())
             {
                 // Network Protocol Listen Response Elements is empty
                 boost::system::error_code ec1 =