Revert "Rename all test files from JS -> ES6"

This reverts commit 2abe85b8344de1102c1589a9ac9421a8b296f2b5.

test/javascripts/components/date-input-test.js

@@ -1,65 +0,0 @@
-import componentTest from "helpers/component-test";
-
-moduleForComponent("date-input", { integration: true });
-
-function dateInput() {
-  return find(".date-picker");
-}
-
-function setDate(date) {
-  this.set("date", date);
-}
-
-async function pika(year, month, day) {
-  await click(
-    `.pika-button.pika-day[data-pika-year="${year}"][data-pika-month="${month}"][data-pika-day="${day}"]`
-  );
-}
-
-function noop() {}
-
-const DEFAULT_DATE = new Date(2019, 0, 29);
-
-componentTest("default", {
-  template: `{{date-input date=date}}`,
-
-  beforeEach() {
-    this.setProperties({ date: DEFAULT_DATE });
-  },
-
-  test(assert) {
-    assert.equal(dateInput().val(), "January 29, 2019");
-  }
-});
-
-componentTest("prevents mutations", {
-  template: `{{date-input date=date onChange=onChange}}`,
-
-  beforeEach() {
-    this.setProperties({ date: DEFAULT_DATE });
-    this.set("onChange", noop);
-  },
-
-  async test(assert) {
-    await click(dateInput());
-    await pika(2019, 0, 2);
-
-    assert.ok(this.date.getTime() === DEFAULT_DATE.getTime());
-  }
-});
-
-componentTest("allows mutations through actions", {
-  template: `{{date-input date=date onChange=onChange}}`,
-
-  beforeEach() {
-    this.setProperties({ date: DEFAULT_DATE });
-    this.set("onChange", setDate);
-  },
-
-  async test(assert) {
-    await click(dateInput());
-    await pika(2019, 0, 2);
-
-    assert.ok(this.date.getTime() === new Date(2019, 0, 2).getTime());
-  }
-});