Update dependency ember-data to v5.6.0

Author: renovate[bot]

package.json

@@ -96,7 +96,7 @@
     "ember-click-outside": "6.1.1",
     "ember-concurrency": "4.0.4",
     "ember-css-modules": "2.1.1",
-    "ember-data": "5.5.0",
+    "ember-data": "5.6.0",
     "ember-disable-prototype-extensions": "1.1.3",
     "ember-error-route": "0.2.0",
     "ember-event-helpers": "0.1.1",