chore(deps-dev): update flask requirement from <4,>=1 to >=3.1.3,<4

[dependabot]

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Updates the requirements on flask to permit the latest version.

Release notes

Sourced from flask's releases.

3.1.3

This is the Flask 3.1.3 security fix release, which fixes a security issue but does not otherwise change behavior and should not result in breaking changes compared to the latest feature release.

PyPI: https://pypi.org/project/Flask/3.1.3/ Changes: https://flask.palletsprojects.com/page/changes/#version-3-1-3

• The session is marked as accessed for operations that only access the keys but not the values, such as in and len. GHSA-68rp-wp8r-4726

Changelog

Sourced from flask's changelog.

Version 3.1.3

Released 2026-02-18

• The session is marked as accessed for operations that only access the keys but not the values, such as in and len. :ghsa:68rp-wp8r-4726

Version 3.1.2

Released 2025-08-19

• stream_with_context does not fail inside async views. :issue:5774
• When using follow_redirects in the test client, the final state of session is correct. :issue:5786
• Relax type hint for passing bytes IO to send_file. :issue:5776

Version 3.1.1

Released 2025-05-13

• Fix signing key selection order when key rotation is enabled via SECRET_KEY_FALLBACKS. :ghsa:4grg-w6v8-c28g
• Fix type hint for cli_runner.invoke. :issue:5645
• flask --help loads the app and plugins first to make sure all commands are shown. :issue:5673
• Mark sans-io base class as being able to handle views that return AsyncIterable. This is not accurate for Flask, but makes typing easier for Quart. :pr:5659

Version 3.1.0

Released 2024-11-13

• Drop support for Python 3.8. :pr:5623
• Update minimum dependency versions to latest feature releases. Werkzeug >= 3.1, ItsDangerous >= 2.2, Blinker >= 1.9. :pr:5624,5633
• Provide a configuration option to control automatic option responses. :pr:5496
• Flask.open_resource/open_instance_resource and Blueprint.open_resource take an encoding parameter to use when opening in text mode. It defaults to utf-8. :issue:5504
• Request.max_content_length can be customized per-request instead of only through the MAX_CONTENT_LENGTH config. Added

... (truncated)

Commits

• 22d9247 release version 3.1.3
• 089cb86 Merge commit from fork
• c17f379 request context tracks session access
• 27be933 start version 3.1.3
• 4e652d3 Abort if the instance folder cannot be created (#5903)
• 3d03098 Abort if the instance folder cannot be created
• 407eb76 document using gevent for async (#5900)
• ac5664d document using gevent for async
• 4f79d5b Increase required flit_core version to 3.11 (#5865)
• fe3b215 Increase required flit_core version to 3.11
• Additional commits viewable in compare view

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.34%. Comparing base (6dd69f8) to head (827df79).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1525   +/-   ##
=======================================
  Coverage   91.34%   91.34%           
=======================================
  Files         228      228           
  Lines        7279     7279           
=======================================
  Hits         6649     6649           
  Misses        630      630           

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