**Apache Airflow version**: 1.10.11

**Environment**: Python 3.7

- **Cloud provider or hardware configuration**:
- **OS** (e.g. from /etc/os-release): PRETTY_NAME="Debian GNU/Linux 10 (buster)"
 (from python3.7-slim-buster docker image)
- **Kernel** (e.g. `uname -a`): Linux 5.4.0-42-generic #46-Ubuntu SMP Fri Jul 10 00:24:02 UTC 2020 x86_64 GNU/Linux
- **Install tools**:
- **Others**:

**What happened**:

Using a markdown formatted table does not work.

**What you expected to happen**:

To be able to see a formated table within DAG view

**How to reproduce it**:

Add a tabular formatted code do dag.doc_md.

Example:

> mytable:
> 
> | a | b | c |
> | ------------- | ------------- | ------------- |
> | a | b | c |

[Table not formatted](https://i.imgur.com/l6JXuWe.png)

**Anything else we need to know**: N/A

tests/www/test_utils.py
def setUp(self):
        self.attr_renderer = utils.get_attr_renderer()
    def test_python_callable(self):
        def example_callable(unused_self):
            print("example")
        rendered = self.attr_renderer["python_callable"](example_callable)
        self.assertIn('&quot;example&quot;', rendered)
    def test_python_callable_none(self):
        rendered = self.attr_renderer["python_callable"](None)
        self.assertEqual("", rendered)
    def test_markdown(self):
        markdown = "* foo\n* bar"
        rendered = self.attr_renderer["doc_md"](markdown)
        self.assertIn("<li>foo</li>", rendered)
        self.assertIn("<li>bar</li>", rendered)
    def test_markdown_none(self):
        rendered = self.attr_renderer["python_callable"](None)
        self.assertEqual("", rendered)
class TestWrappedMarkdown(unittest.TestCase):
    def test_wrapped_markdown_with_docstring_curly_braces(self):
        rendered = wrapped_markdown("{braces}", css_class="a_class")
        self.assertEqual('<div class="a_class" ><p>{braces}</p></div>', rendered)
    def test_wrapped_markdown_with_some_markdown(self):
        rendered = wrapped_markdown("*italic*\n**bold**\n", css_class="a_class")
        self.assertEqual(
            '''<div class="a_class" ><p><em>italic</em>
<strong>bold</strong></p></div>''',
            rendered,
        )