chore(deps): bump actions/upload-artifact from 5 to 6

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 5 to 6.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v5...v6)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/metadata-parser-validation.yml

@@ -48,7 +48,7 @@ jobs:
       with:
         args: 'lint transformed_${{ matrix.version }}_${{ matrix.settings }}_metadata.yml --skip-rule operation-4xx-response --skip-rule no-server-trailing-slash --skip-rule no-unused-components --skip-rule security-defined --skip-rule info-license-url --skip-rule info-license --skip-rule no-empty-servers --skip-rule operation-summary --skip-rule tag-description --max-problems 1000'
 
-    - uses: actions/upload-artifact@v5
+    - uses: actions/upload-artifact@v6
       if: always()
       with:
         name: ${{ matrix.version }}-${{ matrix.settings }}

.github/workflows/validate-typespec-changes.yml

@@ -29,7 +29,7 @@ jobs:
       - name: build typespec
         run: tsp compile .
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         if: always()
         with:
           name: CSDLs