build(deps-dev): update django-mptt requirement from ~=0.13.4 to >=0.13.4,<0.15.0

[dependabot]

Updates the requirements on django-mptt to permit the latest version.

Changelog

Sourced from django-mptt's changelog.

========== Change log

Next version

0.14

• Merged the docs/upgrade.rst file into the main CHANGELOG.rst.
• Fixed the Sphinx autodoc configuration to also work locally. Ensured that readthedocs is able to build the docs again.
• Fixed a bug where DraggableMPTTAdmin assumed that the user model's primary key is called id.
• Ensured that we do not install the tests.myapp package.
• Added dark mode support to the draggable model admin.
• Started using pre-commit, for the fun of it.

0.13

• MARKED THE PROJECT AS UNMAINTAINED, WHICH IT STILL IS
• Reformatted everything using black, isort etc.
• Switched from Travis CI to GitHub actions.
• Switched to a declarative setup.
• Verified compatibility with Django up to 3.2 and Python up to 3.9. Dropped compatibility guarantees (ha!) with anything older than Django 2.2 and Python 3.6.
• Renamed the main development branch to main.
• Fixed a problem where our _get_user_field_names mistakenly returned abstract fields.
• Added a workaround for the default_app_config warning.
• Changed saving to always call get_ordered_insertion_target when using ordered insertion.
• Made it possible to override the starting level when using the tree node choice field.

0.12

• Add support for Django 3.1
• Drop support for Django 1.11.
• Drop support for Python 3.5.
• Fix an issue where the rebuild() method would not work correctly if you were using multiple databases.
• Update spanish translations.

0.11

... (truncated)

Commits

• 593bbeb django-mptt 0.14
• 9c22b41 More versions
• fa08552 pre-commit autoupdate
• be073ed Merge pull request #818 from PetrDlouhy/fix_memory_leak
• f8facf1 fix memory error with large levels, add tests
• 5e72cd2 Merge pull request #817 from timoludwig/readme
• 048ab89 Point out unclear maintenance of django-treebeard
• 74ab24b Add pre-commit
• 72d46cf Merge pull request #815 from timgates42/bugfix_typos
• 9454a4a docs: Fix a few typos
• Additional commits viewable in compare view

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[dependabot]

The following labels could not be found: type:maintenance.

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