chore: do not print stacktraces for defined error states when publishing extensions (#1485)

Author: netomi

server/src/main/java/org/eclipse/openvsx/RegistryAPI.java

@@ -1251,7 +1251,7 @@ public ResponseEntity<ExtensionJson> publish(
                     .location(URI.create(url))
                     .body(json);
         } catch (ErrorResultException exc) {
-            logger.warn("Failed to publish extension", exc);
+            logger.warn("Failed to publish extension: {}", exc.getMessage());
             return exc.toResponseEntity(ExtensionJson.class);
         }
     }
@@ -1304,7 +1304,7 @@ public ResponseEntity<ExtensionJson> publish(InputStream content) {
                     .location(URI.create(url))
                     .body(json);
         } catch (ErrorResultException exc) {
-            logger.warn("Failed to publish extension", exc);
+            logger.warn("Failed to publish extension: {}", exc.getMessage());
             return exc.toResponseEntity(ExtensionJson.class);
         }
     }