Update dependency ring:ring-core to v1.15.3

Author: renovate[bot]

project.clj

@@ -197,7 +197,7 @@
                          [prismatic/schema "1.4.1"]
                          [riddley "0.2.0"]
                          [ring/ring-codec "1.3.0"]
-                         [ring/ring-core "1.8.2"]
+                         [ring/ring-core "1.15.3"]
                          [ring/ring-mock "0.4.0"]
                          [robert/hooke "1.3.0"]
                          [timofreiberg/bultitude "0.3.1"]