Removed browserkit from a couple of classess

Done a little reorganisation while there of misplaced tests.
Moved MarkdownTest to a new PageEditorTest to avoid confusion with
other markdown elements and to align with other page tests.

tests/Entity/PageEditorTest.php

@@ -0,0 +1,52 @@
+<?php
+
+namespace Tests\Entity;
+
+use BookStack\Entities\Models\Page;
+use Tests\TestCase;
+
+class PageEditorTest extends TestCase
+{
+    /** @var Page  */
+    protected $page;
+
+    public function setUp(): void
+    {
+        parent::setUp();
+        $this->page = Page::query()->first();
+    }
+
+    public function test_default_editor_is_wysiwyg()
+    {
+        $this->assertEquals('wysiwyg', setting('app-editor'));
+        $this->asAdmin()->get($this->page->getUrl() . '/edit')
+            ->assertElementExists('#html-editor');
+    }
+
+    public function test_markdown_setting_shows_markdown_editor()
+    {
+        $this->setSettings(['app-editor' => 'markdown']);
+        $this->asAdmin()->get($this->page->getUrl() . '/edit')
+            ->assertElementNotExists('#html-editor')
+            ->assertElementExists('#markdown-editor');
+    }
+
+    public function test_markdown_content_given_to_editor()
+    {
+        $this->setSettings(['app-editor' => 'markdown']);
+
+        $mdContent = '# hello. This is a test';
+        $this->page->markdown = $mdContent;
+        $this->page->save();
+
+        $this->asAdmin()->get($this->page->getUrl() . '/edit')
+            ->assertElementContains('[name="markdown"]', $mdContent);
+    }
+
+    public function test_html_content_given_to_editor_if_no_markdown()
+    {
+        $this->setSettings(['app-editor' => 'markdown']);
+        $this->asAdmin()->get($this->page->getUrl() . '/edit')
+            ->assertElementContains('[name="markdown"]', $this->page->html);
+    }
+}