
**Apache Airflow version**:
2.0.1

**Environment**:

- **OS**: Linux Mint 19.2 
- **Kernel**: 5.5.0-050500-generic #202001262030 SMP Mon Jan 27 01:33:36 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

**What happened**:

Seems that pagination doesn't work. I filter DAGs by tags and get too many results to get them at one page. When I click second page I'm redirected to the first one (actually, it doesn't matter if I click second, last or any other - I'm always getting redirected to the first one).

**What you expected to happen**:

I expect to be redirected to the correct page when I click number on the bottom of the page.

**How to reproduce it**:
1. Create a lot of DAGs with the same tag
2. Filter by tag
3. Go to the next page in the pagination bar

**Implementation example**:



```
from airflow import DAG
from airflow.utils.dates import days_ago
for i in range(200):
    name = 'test_dag_' + str(i)
    dag = DAG(
        dag_id=name,
        schedule_interval=None,
        start_date=days_ago(2),
        tags=['example1'],
    )
    globals()[name] = dag
```

tests/www/test_utils.py
rendered = wrapped_markdown("*italic*\n**bold**\n", css_class="a_class")
        assert (
            '''<div class="a_class" ><p><em>italic</em>
<strong>bold</strong></p></div>'''
            == rendered
        )
    def test_wrapped_markdown_with_table(self):
        rendered = wrapped_markdown(
            """| Job | Duration |
               | ----------- | ----------- |
               | ETL | 14m |"""
        )
        assert (
            '<div class="rich_doc" ><table>\n<thead>\n<tr>\n<th>Job</th>\n'
            '<th>Duration</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ETL'
            '</td>\n<td>14m</td>\n</tr>\n</tbody>\n'
            '</table></div>'
        ) == rendered
    def test_wrapped_markdown_with_indented_lines(self):
        rendered = wrapped_markdown(
            """
                # header
                1st line
                2nd line
            """
        )
        assert '<div class="rich_doc" ><h1>header</h1>\n<p>1st line\n2nd line</p></div>' == rendered