fix: use bold text instead of headings in changeset body

Author: quantizor

.changeset/stabilization-v7.md

@@ -2,25 +2,29 @@
 "jest-styled-components": minor
 ---
 
-### Security
+**Security**
+
 - Bump `@adobe/css-tools` to ^4.4.0, fixing CVE-2023-48631 (ReDoS) and adding `@starting-style` support
 
-### Bug Fixes
+**Bug Fixes**
+
 - Fix null/undefined children crash in snapshot serializer
 - Fix `@media` query whitespace mismatch in `toHaveStyleRule`
 - Normalize spaces after commas in CSS value comparison (fixes `rgb()` and `font-family` mismatches)
 - Add word boundaries to class name replacement regex to prevent partial matches
 - Fix Enzyme shallow rendering assertion for nested styled children on SC v6
 - Guard `expect` and `beforeEach` calls for Vitest/Bun non-globals mode compatibility
 
-### Features
+**Features**
+
 - Add `selector` option to `toHaveStyleRule` for testing `createGlobalStyle` styles
 - Add Vitest entry point (`jest-styled-components/vitest`) with types
 - Add TypeScript declarations for `jest-styled-components/serializer` and `jest-styled-components/native` subpaths
 - Export `resetStyleSheet` for manual test setup in non-Jest environments
 - Add JSDoc comments to all type declarations
 
-### Infrastructure
+**Infrastructure**
+
 - Adopt changesets for versioning and releases
 - Add provenance-based release workflow via GitHub Actions
 - Update GitHub Actions to v4 (checkout, setup-node, cache) and CodeQL to v3