Bump idna from 3.11 to 3.15 in /maintenance

[dependabot]

Bumps idna from 3.11 to 3.15.

Changelog

Sourced from idna's changelog.

3.15 (2026-05-12)

• Enforce DNS-length cap on individual labels early in check_label, short-circuiting contextual-rule processing for oversized input while staying compatible with UTS 46 usage.
• Tidy core helpers: hoist bidi category sets to module-level frozensets (avoiding per-codepoint list construction), simplify length checks, and reuse the shared _unicode_dots_re from idna.core in the codec module.
• Use raise ... from err for proper exception chaining and switch internal string formatting to f-strings.
• Allow flit_core 4.x in the build backend.
• Expand the ruff lint set (flake8-bugbear, flake8-simplify, pyupgrade, perflint) and apply the surfaced fixes; pin lint CI to Python 3.14.
• Add Dependabot configuration for GitHub Actions.
• Convert README and HISTORY from reStructuredText to Markdown.
• Reference CVE-2026-45409 for the 3.14 advisory in place of the initial GHSA identifier.

Thanks to Felix Yan, Stan Ulbrych, and metsw24-max for contributions to this release.

3.14 (2026-05-10)

• Removed opportunity to process long inputs into quadratic time by rejecting oversize inputs up-front. Closes a bypass of the CVE-2024-3651 mitigation. [CVE-2026-45409]

Thanks to Stan Ulbrych for reporting the issue.

3.13 (2026-04-22)

• Correct classification error for codepoint U+A7F1

3.12 (2026-04-21)

• Update to Unicode 17.0.0.
• Issue a deprecation warning for the transitional argument.
• Added lazy-loading to provide some performance improvements.
• Removed vestiges of code related to Python 2 support, including segmentation of data structures specific to Jython.

Thanks to Rodrigo Nogueira for contributions to this release.

Commits

• af30a09 Release 3.15
• 30314d4 Pre-release 3.15rc0
• 05d4b21 Merge pull request #237 from kjd/convert-docs-to-markdown
• 2987fdb Convert README and HISTORY from reStructuredText to Markdown
• 59fa800 Merge pull request #236 from kjd/dependabot/github_actions/actions-f3e34333ea
• def6983 Merge branch 'master' into dependabot/github_actions/actions-f3e34333ea
• bbd8004 Merge pull request #234 from StanFromIreland/patch-1
• edd07c0 Bump github/codeql-action from 3.35.2 to 4.35.2 in the actions group
• 5557db0 Merge branch 'master' into patch-1
• f11746c Merge pull request #235 from StanFromIreland/patch-2
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
  You can disable automated security fix PRs for this repo from the Security Alerts page.

---

This change is 

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.95%. Comparing base (99d9257) to head (873647e).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4290   +/-   ##
=======================================
  Coverage   75.95%   75.95%           
=======================================
  Files         304      304           
  Lines       11372    11372           
  Branches     1405     1405           
=======================================
  Hits         8638     8638           
  Misses       2332     2332           
  Partials      402      402           

Flag	Coverage Δ
backend	87.22% <ø> (ø)
frontend	66.85% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[dependabot]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version. You can also ignore all major, minor, or patch releases for a dependency by adding an ignore condition with the desired update_types to your config file.

If you change your mind, just re-open this PR and I'll resolve any conflicts on it.