drop support for Ember < 3.20 (#70)

Author: jelhan

.github/workflows/ci.yml

@@ -54,9 +54,7 @@ jobs:
       fail-fast: false
       matrix:
         try-scenario:
-          - ember-lts-3.4
-          - ember-lts-3.8
-          - ember-lts-3.16
+          - ember-lts-3.20
           - ember-lts-3.24
           - ember-lts-3.28
 

README.md

@@ -6,11 +6,10 @@ Test helper to simulate browsers back and forward buttons in acceptance tests.
 Compatibility
 ------------------------------------------------------------------------------
 
-* Ember.js v3.4 or above
-* Ember CLI v2.13 or above
+* Ember.js v3.20 or above
+* Ember CLI v3.20 or above
 * Node.js v12 or above
 
-
 Installation
 ------------------------------------------------------------------------------
 

config/ember-try.js

@@ -7,26 +7,10 @@ module.exports = async function() {
     useYarn: true,
     scenarios: [
       {
-        name: 'ember-lts-3.4',
+        name: 'ember-lts-3.20',
         npm: {
           devDependencies: {
-            'ember-source': '~3.4.0'
-          }
-        }
-      },
-      {
-        name: 'ember-lts-3.8',
-        npm: {
-          devDependencies: {
-            'ember-source': '~3.8.0'
-          }
-        }
-      },
-      {
-        name: 'ember-lts-3.16',
-        npm: {
-          devDependencies: {
-            'ember-source': '~3.16.0'
+            'ember-source': '~3.20.0'
           }
         }
       },