Upgrade pitest-maven-plugin 1.15.8 -> 1.16.0

[Picnic-Bot]

This PR contains the following updates:

Package	Type	Update	Change
pitest-maven-plugin (source)	build	minor	1.15.8 -> 1.16.0

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Release Notes

hcoles/pitest (pitest-maven-plugin)

v1.16.0

Compare Source

• #​1311 - Include unmodifiable collections stored directly to fields in the +funmodifiablecollection filter for defensive code
• #​1319 - Use environment variables from surefire config
• #​1322 - Automatically add -ea to enable assertions
• #​1321 - Expand BuildVerifier interface

Api change in #​1321 is backwards compatible, but plugins written against 1.16.0 may not work with earlier versions.

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• If you want to rebase/retry this PR, check this box

[Picnic-Bot]

Suggested commit message:

Upgrade pitest-maven-plugin 1.15.8 -> 1.16.0 (#1127)

See:
- https://github.com/hcoles/pitest/releases/tag/1.16.0
- https://github.com/hcoles/pitest/compare/1.15.8...1.16.0

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[github-actions]

Looks good. No mutations were possible for these changes.
Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

[Stephan202]

Output appears unchanged.