Bump astral-sh/setup-uv from 6 to 7 (smithy-lang#569)

Bumps [astral-sh/setup-uv](https://github.com/astral-sh/setup-uv) from 6 to 7.
- [Release notes](https://github.com/astral-sh/setup-uv/releases)
- [Commits](astral-sh/setup-uv@v6...v7)

---
updated-dependencies:
- dependency-name: astral-sh/setup-uv
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -37,7 +37,7 @@ jobs:
         uses: gradle/actions/setup-gradle@v4
 
       - name: Install uv
-        uses: astral-sh/setup-uv@v6
+        uses: astral-sh/setup-uv@v7
         with:
           activate-environment: true