build(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] <[email protected]>

Author: dependabot[bot]

.github/workflows/build.yml

@@ -40,7 +40,7 @@ jobs:
           ./waf docs_sdk
 
       - name: Publish docs artifact
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: docs-c
           path: |
@@ -63,7 +63,7 @@ jobs:
           ./gradlew releaseJavadoc
 
       - name: Publish docs artifact
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: docs-android
           path: PebbleKit/PebbleKit/build/docs/javadoc
@@ -79,7 +79,7 @@ jobs:
           repository: pebble/pebble-ios-sdk
 
       - name: Publish docs artifact
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: docs-ios
           path: PebbleKit-iOS.docset/Contents/Resources/Documents

.github/workflows/test.yml

@@ -23,7 +23,7 @@ jobs:
           SKIP_DOCS: true # TODO: remove once we can get docs artifacts in here easily
 
       - name: Upload report artifact
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         if: always()
         with:
           name: test-report