Bump django-treebeard from 4.3.1 to 4.5.1

[dependabot]

Bumps django-treebeard from 4.3.1 to 4.5.1.

Changelog

Sourced from django-treebeard's changelog.

Release 4.5.1 (Feb 22, 2021)

• Removed unnecessary default in MP's depth field.

Release 4.5 (Feb 17, 2021)

• Add support for custom primary key fields with custom names.
• Add support for Python 3.9.
• Add support for MSSQL 2019.
• Add Code of conduct
• Removed outdated Sqlite workaround code
• Remove last remains of Python 2.7 code
• Use Pytest-django and fixtures for testing

Release 4.4 (Jan 13, 2021)

• Implement a non-destructive path-fixing algorithm for MP_Node.fix_tree.
• Ensure post_save is triggered after the parent node is updated in MP_AddChildHandler.
• Fix static URL generation to use static template tag instead of constructing the URL manually.
• Declare support for Django 2.2, 3.0 and 3.1.
• Drop support for Django 2.1 and lower.
• Drop support for Python 2.7 and Python 3.5.
• Increase performance for MoveNodeForm when using large trees.

Commits

• 755c85e Bump to 4.5.1
• 551a69c Merge pull request #215 from django-treebeard/211-no-migrations
• b2ba36f Reverting unnecesary default in mp depth field
• 64e48cf Bump to version 4.5
• bc441c0 Merge pull request #209 from johanneswilm/patch-1
• afcebd3 Update CHANGES.md for 4.5
• 780c248 Merge pull request #208 from django-treebeard/206-revamp-testing
• 983cc7a Updated tests to leverage more of modern pytest fixtures
• ad2b37a #206 Modernizing test infra, now using pytest-django and fixtures
• 8cf3cb5 CHANGES was renamed, fix reference in docs
• Additional commits viewable in compare view

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[dependabot]

The following labels could not be found: dependencies, backport 3.x.

[dependabot]

Superseded by #708.