[VAULT-34699] UI: Remove FormError component (not used) (#29930)

* [UI] removed `FormError` component (not used) (#34699)

* added changelog

changelog/34699.txt

@@ -0,0 +1,3 @@
+```release-note:change
+ui: Removed `FormError` component (not used)
+```

ui/lib/core/addon/components/form-error.hbs

@@ -1,13 +0,0 @@
-{{!
-  Copyright (c) HashiCorp, Inc.
-  SPDX-License-Identifier: BUSL-1.1
-}}
-
-<div class="has-top-margin-s is-flex is-flex-center" data-test-form-error>
-  <div class="is-narrow message-icon">
-    <Icon @name="x-square-fill" class="has-text-danger" />
-  </div>
-  <div class="has-text-danger">
-    {{yield}}
-  </div>
-</div>

ui/lib/core/app/components/form-error.js

@@ -1,6 +0,0 @@
-/**
- * Copyright (c) HashiCorp, Inc.
- * SPDX-License-Identifier: BUSL-1.1
- */
-
-export { default } from 'core/components/form-error';

ui/tests/integration/components/form-error-test.js

@@ -1,31 +0,0 @@
-/**
- * Copyright (c) HashiCorp, Inc.
- * SPDX-License-Identifier: BUSL-1.1
- */
-
-import { module, test } from 'qunit';
-import { setupRenderingTest } from 'ember-qunit';
-import { render } from '@ember/test-helpers';
-import hbs from 'htmlbars-inline-precompile';
-
-module('Integration | Component | form-error', function (hooks) {
-  setupRenderingTest(hooks);
-
-  test('it renders', async function (assert) {
-    // Set any properties with this.set('myProperty', 'value');
-    // Handle any actions with this.set('myAction', function(val) { ... });
-
-    await render(hbs`{{form-error}}`);
-
-    assert.dom(this.element).hasText('');
-
-    // Template block usage:
-    await render(hbs`
-      <FormError>
-        template block text
-      </FormError>
-    `);
-
-    assert.dom(this.element).hasText('template block text');
-  });
-});