**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
self.assertTrue(utils.should_hide_value_for_key("google_api_key"))
    def test_sensitive_variable_should_be_hidden_ic(self):
        self.assertTrue(utils.should_hide_value_for_key("GOOGLE_API_KEY"))
    @parameterized.expand(
        [
            ('key', 'TRELLO_KEY', True),
            ('key', 'TRELLO_API_KEY', True),
            ('key', 'GITHUB_APIKEY', True),
            ('key, token', 'TRELLO_TOKEN', True),
            ('mysecretword, mysensitivekey', 'GITHUB_mysecretword', True),
        ],
    )
    def test_sensitive_variable_fields_should_be_hidden(
        self, sensitive_variable_fields, key, expected_result
    ):
        with conf_vars({('admin', 'sensitive_variable_fields'): str(sensitive_variable_fields)}):
            self.assertEqual(expected_result, utils.should_hide_value_for_key(key))
    @parameterized.expand(
        [
            (None, 'TRELLO_API', False),
            ('token', 'TRELLO_KEY', False),
            ('token, mysecretword', 'TRELLO_KEY', False),
        ],
    )
    def test_normal_variable_fields_should_not_be_hidden(
        self, sensitive_variable_fields, key, expected_result
    ):
        with conf_vars({('admin', 'sensitive_variable_fields'): str(sensitive_variable_fields)}):
            self.assertEqual(expected_result, utils.should_hide_value_for_key(key))
    def check_generate_pages_html(self, current_page, total_pages, window=7, check_middle=False):