[Discover] Broken back navigation in context when filter contains whitespace

[kertal]

Kibana version:
master, 7.7, 7.6, ..., 6.8, ...?

Describe the bug:

This bug has been there for a long time. When you add a filter in Discover that contains a whitespace, navigate to context view aka surrounding documents, you can't navigate back with the browser's back button.

Steps to reproduce:

1. Use kibana_sample_data_logs
2. Navigate to Discover
3. Add a filter for an agent field (those usually contain whitespaces)
4. Expand a document and click on "View surrounding documents"
5. Try to navigate back with the browsers back button
6. Doesn't work in Chrome, Firefox

Expected behavior:

Back button should work

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)