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/build.yml

@@ -45,7 +45,7 @@ jobs:
         run: ./gradlew testAndReport -PspringBootVersion=${{ matrix.boot }} -PspringFrameworkVersion=${{ matrix.framework }}
 
       - name: Upload Artifact
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         if: always()
         with:
           name: report-java-${{ matrix.java }}-spring-boot-${{ matrix.boot }}
@@ -75,7 +75,7 @@ jobs:
         run: ./gradlew testAndReport
 
       - name: Upload Artifact
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         if: always()
         with:
           name: report-java-${{ matrix.java }}-spring-boot-latest
@@ -139,7 +139,7 @@ jobs:
         run: ./gradlew build -x test
 
       - name: Upload Artifact
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: jar
           path: build/libs/**