[AIRFLOW-5086] Fix search for partial string in classic UI

[feluelle]

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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-5086
  • 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.
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Description

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Since 1.10.3 it is not possible to search for a partial string (dag_id or author). This fixes it so you can search for partial matching dag_id's or authors.

Tests

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

Commits

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  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
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Code Quality

• Passes flake8