[AIRFLOW-1523] Clicking on Graph View should display related DAG run

[JCoder01]

Add execution_date_arg
Use execution_date_arg in graph, gantt, and Back To {parent.dag} links.

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • https://issues.apache.org/jira/browse/AIRFLOW-1523
  • In case you are fixing a typo in the documentation you can prepend your commit with [AIRFLOW-XXX], code changes always need a Jira issue.
  • In case you are proposing a fundamental code change, you need to create an Airflow Improvement Proposal (AIP).
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Description

• Here are some details about my PR, including screenshots of any UI changes:
  Currently, in the dag view, execution_date is not included as query param for the Graph or Gantt Chart views. It also is not included as part of the Back To {{ parentdag }} link. This PR adds execution_date to the query params;

Before:

After:

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:
  Current tests cover changes

Commits

• My commits all reference Jira issues in their subject lines, and I have squashed multiple commits if they address the same issue. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation

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  • All the public functions and the classes in the PR contain docstrings that explain what it does
  • If you implement backwards incompatible changes, please leave a note in the Updating.md so we can assign it to a appropriate release

Code Quality

• Passes flake8

[kaxil]

LGTM. But tagging in @ashb as well.