abstract out the stripe component for easy future testing

test/javascripts/components/donation-form-test.es6

@@ -5,10 +5,12 @@ moduleForComponent("donation-form", { integration: true });
 componentTest("donation form has content", {
   template: `{{donation-form}}`,
 
+  beforeEach() {
+    this.registry.register('component:stripe-card', Ember.Component.extend({ tagName: 'dummy-component-tag' }));
+  },
+
   async test(assert) {
-    assert.ok(find('#payment-form').length, 'The form renders');
-    assert.equal(find('.discourse-donations-cause .selected-name')
-      .text()
-      .trim(), 'Select a cause', 'It has the combo box');
+    assert.ok(find('#payment-form').length, "The form renders");
+    assert.ok(find('dummy-component-tag').length, "The stripe component renders");
   }
 });

test/javascripts/components/donation-row-test.js.es6

@@ -6,9 +6,9 @@ componentTest("donation-row", {
   template: `{{donation-row currency=3 amount=21 period='monthly'}}`,
 
   test(assert) {
-    assert.equal(find(".donation-row-currency").text(), "3");
-    assert.equal(find(".donation-row-amount").text(), "21");
-    assert.equal(find(".donation-row-period").text(), "monthly");
+    assert.equal(find(".donation-row-currency").text(), "3", "It has currency");
+    assert.equal(find(".donation-row-amount").text(), "21", "It has an amount");
+    assert.equal(find(".donation-row-period").text(), "monthly", "It has a period");
   }
 });
 
@@ -21,6 +21,6 @@ componentTest("donation-row cancels subscription", {
   },
 
   async test(assert) {
-    assert.ok(find(".donation-row-subscription").length);
+    assert.ok(find(".donation-row-subscription").length, "It has a subscription");
   }
 });