chore(deps-dev): update phpunit/phpunit requirement from ^11.5 to ^13.1

[dependabot]

Updates the requirements on phpunit/phpunit to permit the latest version.

Release notes

Sourced from phpunit/phpunit's releases.

PHPUnit 13.1.13

Fixed

• #6681: XML assertions such as assertXmlStringEqualsXmlString() regressed into treating comments as significant

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Changelog

Sourced from phpunit/phpunit's changelog.

[13.1.13] - 2026-05-27

Fixed

• #6681: XML assertions such as assertXmlStringEqualsXmlString() regressed into treating comments as significant

[13.1.12] - 2026-05-25

Fixed

• #6673: Empty PHP settings from the parent process override per-test -d settings forwarded to child processes (breaks PCOV coverage)

[13.1.11] - 2026-05-21

Fixed

• PHP setting values containing = need to be quoted before forwarding via -d

[13.1.10] - 2026-05-15

Changed

• Pass configuration options introduced in sebastian/diff 8.3.0

[13.1.9] - 2026-05-13

Changed

• A Test or Tests prefix is no longer stripped from class names when they are processed for TestDox output

Fixed

• #6605: Data set names and provider values containing Unicode bidirectional control characters distort terminal output
• #6610: Per-testsuite bootstrap script not loaded in process isolation
• TestDox output collapsed separate test classes into a single group when their prettified class names matched

[13.1.8] - 2026-05-01

Fixed

• #6595: Crash when before-class or after-class method fails with assertion failure
• #6599: TeamCity logger does not wrap failures in before-test methods with testStarted and testFinished
• #6601: Anonymous classes are not rejected with a clear error when creating a test double
• #6603: assertArrays*IgnoringOrder() fails on mixed scalar types and on reordered nested associative arrays
• MockBuilder::setMockClassName() and TestStubBuilder::setStubClassName() now reject values that are not valid unqualified PHP class identifiers, throwing the new InvalidClassNameException
• The regular expression used by Generator::ensureValidMethods() to validate method names passed to MockBuilder::onlyMethods() and addMethods() was not anchored, so any string containing a valid identifier substring (including strings with parentheses, braces, comments, or newlines) was accepted

[13.1.7] - 2026-04-18

Changed

... (truncated)

Commits

• ddf7f25 Prepare release
• c8cfb2b Merge branch '12.5' into 13.1
• 5895d05 Prepare release
• 9f0a329 Merge branch '12.5' into 13.1
• 9bbd824 Merge branch '11.5' into 12.5
• cb389c9 Merge branch '10.5' into 11.5
• b277f5d Merge branch '9.6' into 10.5
• c26c080 Merge branch '8.5' into 9.6
• ab649af Update dependencies
• 86a9a41 Merge branch '12.5' into 13.1
• Additional commits viewable in compare view

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.96%. Comparing base (7a40e2f) to head (bbba9de).

Additional details and impacted files

@@              Coverage Diff              @@
##                main      #43      +/-   ##
=============================================
- Coverage     100.00%   98.96%   -1.04%     
  Complexity       836      836              
=============================================
  Files             76       76              
  Lines           1744     1736       -8     
=============================================
- Hits            1744     1718      -26     
- Misses             0       18      +18     

see 15 files with indirect coverage changes