ring/ring-core: pin to 1.15.3

```
Possibly confusing dependencies found:
[compojure "1.7.2"] -> [ring/ring-core "1.15.1"]
 overrides
[org.openvoxproject/trapperkeeper-webserver-jetty10 "1.1.2"] -> [ring/ring-servlet "1.15.3"] -> [ring/ring-core "1.15.3"]

Consider using these :managed-dependencies:
[ring/ring-core "1.15.3"]

[compojure "1.7.2"] -> [ring/ring-core "1.15.1"] -> [org.ring-clojure/ring-core-protocols "1.15.1"]
 overrides
[org.openvoxproject/trapperkeeper-webserver-jetty10 "1.1.2"] -> [ring/ring-servlet "1.15.3"] -> [ring/ring-core "1.15.3"] -> [org.ring-clojure/ring-core-protocols "1.15.3"]

Consider using these :managed-dependencies:
[org.ring-clojure/ring-core-protocols "1.15.3"]

[compojure "1.7.2"] -> [ring/ring-core "1.15.1"] -> [org.ring-clojure/ring-websocket-protocols "1.15.1"]
 overrides
[org.openvoxproject/trapperkeeper-webserver-jetty10 "1.1.2"] -> [ring/ring-servlet "1.15.3"] -> [ring/ring-core "1.15.3"] -> [org.ring-clojure/ring-websocket-protocols "1.15.3"]

Consider using these :managed-dependencies:
[org.ring-clojure/ring-websocket-protocols "1.15.3"]

Aborting due to :pedantic? :abort
```

Author: bastelfreak

project.clj

@@ -10,7 +10,8 @@
                          [ring/ring-codec "1.3.0"]
                          [commons-codec "1.20.0"]
                          [org.slf4j/slf4j-api "2.0.17"]
-                         [cheshire "5.13.0"]]
+                         [cheshire "5.13.0"]
+                         [ring/ring-core "1.15.3"]]
 
   :dependencies [[cheshire]
                  [org.openvoxproject/http-client "2.2.2"]]