Use UTF-8 string literals instead of Encoding.GetBytes in tests

[dennisdoomen]

Changes

1. GitHub Advanced Security follow-up

InspectCode flagged two Encoding.UTF8.GetBytes(...) calls in the new tests added by #163, suggesting UTF-8 string literals instead. Replaced with "..."u8.ToArray() in Cannot_match_body_with_an_unrecognized_content_type_by_default and Can_force_a_body_with_an_unrecognized_content_type_to_be_treated_as_textual, consistent with existing usage elsewhere in HttpMockSpecs.cs.

Note: #163 was merged before these code-scanning comments were addressed, so this is a small follow-up PR against main.

2. Release notes template

Added skip-release-notes to .github/release.yml's changelog.exclude.labels, so PRs labeled skip-release-notes are excluded from auto-generated release notes (same mechanism already used for changelog-ignore).

Testing

• dotnet test --filter "FullyQualifiedName~AdvancedMatching" passes on both net8.0 and net472.
• .github/release.yml is a config-only change (no build/test applicable).

Co-authored-by: Copilot App 223556219+Copilot@users.noreply.github.com

[coveralls]

Coverage Report for CI Build 29336620055

Coverage remained the same at 84.925%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	1515
Covered Lines:	1355
Line Coverage:	89.44%
Relevant Branches:	495
Covered Branches:	352
Branch Coverage:	71.11%
Branches in Coverage %:	Yes
Coverage Strength:	331.93 hits per line

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💛 - Coveralls

[github-actions]

Test Results

  3 files  ±0    3 suites  ±0   8s ⏱️ -1s
199 tests ±0  199 ✅ ±0  0 💤 ±0  0 ❌ ±0 
395 runs  ±0  395 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit b935eef. ± Comparison against base commit 89ac9d9.