Fix ember data deprecations

addon/adapters/version.js

@@ -0,0 +1,18 @@
+import DS from 'ember-data';
+
+export default DS.JSONAPIAdapter.extend({
+  buildURL() {
+    let url = ['content', 'versions.json'];
+    let host = this.host;
+    let prefix = this.urlPrefix();
+
+    if (prefix) { url.unshift(prefix); }
+
+    url = url.join('/');
+    if (!host && url && url.charAt(0) !== '/') {
+      url = '/' + url;
+    }
+
+    return url;
+  },
+});

addon/serializers/application.js

@@ -0,0 +1 @@
+export { default } from '@ember-data/serializer/json-api';

addon/serializers/version.js

@@ -0,0 +1,4 @@
+import JSONAPISerializer from '@ember-data/serializer/json-api';
+
+export default class VersionSerializer extends JSONAPISerializer {
+}

app/adapters/version.js

@@ -1,18 +1,2 @@
-import DS from 'ember-data';
+export { default } from 'guidemaker/adapters/version';
 
-export default DS.JSONAPIAdapter.extend({
-  buildURL() {
-    let url = ['content', 'versions.json'];
-    let host = this.host;
-    let prefix = this.urlPrefix();
-
-    if (prefix) { url.unshift(prefix); }
-
-    url = url.join('/');
-    if (!host && url && url.charAt(0) !== '/') {
-      url = '/' + url;
-    }
-
-    return url;
-  },
-});

app/serializers/application.js

@@ -0,0 +1 @@
+export { default } from 'guidemaker/serializers/application';

app/serializers/version.js

@@ -0,0 +1 @@
+export { default } from 'guidemaker/serializers/version';

package.json

@@ -51,7 +51,6 @@
     "babel-eslint": "^10.0.3",
     "broccoli-asset-rev": "^3.0.0",
     "chai": "^4.2.0",
-    "ember-auto-import": "^1.5.3",
     "ember-cli": "~3.15.1",
     "ember-cli-dependency-checker": "^3.2.0",
     "ember-cli-eslint": "^5.1.0",