fix: Move content into to frontend directory

Doing this BEFORE the merge prevents a lot of merge conflicts.

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

frontend/src/extensions/extra-integrations/vega-lite/vega-lite-markdown-extension.test.tsx

@@ -0,0 +1,41 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { render } from '@testing-library/react'
+import React from 'react'
+import { VegaLiteMarkdownExtension } from './vega-lite-markdown-extension'
+import * as VegaLiteChartModule from '../vega-lite/vega-lite-chart'
+import { mockI18n } from '../../../components/markdown-renderer/test-utils/mock-i18n'
+import type { CodeProps } from '../../../components/markdown-renderer/replace-components/code-block-component-replacer'
+import { TestMarkdownRenderer } from '../../../components/markdown-renderer/test-utils/test-markdown-renderer'
+
+jest.mock('../vega-lite/vega-lite-chart')
+
+describe('Vega-Lite markdown extensions', () => {
+  beforeAll(async () => {
+    jest.spyOn(VegaLiteChartModule, 'VegaLiteChart').mockImplementation((({ code }) => {
+      return (
+        <span>
+          this is a mock for vega lite
+          <code>{code}</code>
+        </span>
+      )
+    }) as React.FC<CodeProps>)
+    await mockI18n()
+  })
+
+  it('renders a vega-lite codeblock', () => {
+    const view = render(
+      <TestMarkdownRenderer
+        extensions={[new VegaLiteMarkdownExtension()]}
+        content={
+          '```vega-lite\n{"$schema":"https://vega.github.io/schema/vega-lite/v4.json","data":{"values":[{"a":"","b":28}]},"mark":"bar","encoding":{"x":{"field":"a"},"y":{"field":"b"}}}\n```'
+        }
+      />
+    )
+    expect(view.container).toMatchSnapshot()
+  })
+})