Add a help doc for the HTML Inspector

Author: mdmintz

help_docs/html_inspector.md

@@ -0,0 +1,36 @@
+<h2><img src="https://seleniumbase.io/img/logo6.png" title="SeleniumBase" width="32" /> The HTML Inspector</h2>
+
+🔵 <b>HTML Inspector</b> provides useful info about a web page.
+
+🔵 (<i>Based on: [github.com/philipwalton/html-inspector](https://github.com/philipwalton/html-inspector)</i>)
+
+🔵 Example: [examples/test_inspect_html.py](https://github.com/seleniumbase/SeleniumBase/blob/master/examples/test_inspect_html.py) (Chromium-only)
+
+```python
+from seleniumbase import BaseCase
+
+class HtmlInspectorTests(BaseCase):
+    def test_html_inspector(self):
+        self.open("https://xkcd.com/1144/")
+        self.inspect_html()
+```
+
+--------
+
+```bash
+pytest test_inspect_html.py 
+============== test session starts ==============
+
+* HTML Inspection Results: https://xkcd.com/1144/
+X - https://xkcd.com/1144/ - Access to XMLHttpRequest at 'https://xkcd.com/usBanner' (redirected from 'https://c.xkcd.com/xkcd/news') from origin 'https://xkcd.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
+X - https://xkcd.com/usBanner - Failed to load resource: net::ERR_FAILED
+X - 'property' is not a valid attribute of the <meta> element.
+X - Do not use <div> or <span> elements without any attributes.
+X - The 'alt' attribute is required for <img> elements.
+X - The 'border' attribute is no longer valid on the <img> element and should not be used.
+X - 'srcset' is not a valid attribute of the <img> element.
+X - The <center> element is obsolete and should not be used.
+X - <script> elements should appear right before the closing </body> tag for optimal performance.
+X - The id 'comicLinks' appears more than once in the document.
+* (See the Console output for details!)
+```

mkdocs.yml

@@ -115,6 +115,7 @@ nav:
     - Docker Start Guide: integrations/docker/ReadMe.md
     - Using Safari Driver: help_docs/using_safari_driver.md
     - Shadow DOM Support: help_docs/shadow_dom.md
+    - The HTML Inspector: help_docs/html_inspector.md
     - macOS Hidden Files: help_docs/hidden_files_info.md
     - MySQL Instructions: help_docs/mysql_installation.md
   - Demo Pages: