.github: update actions/upload_artifact to v4

Author: bk138

.github/workflows/ci.yml

@@ -46,19 +46,19 @@ jobs:
           cpack -V -C Debug
       - name: Archive Ubuntu Build Artifacts
         if: ${{ matrix.os == 'ubuntu-24.04' }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: MultiVNC Debian Package
           path: build/*.deb
       - name: Archive MacOS Build Artifacts
         if: ${{ matrix.os == 'macos-latest' }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: MultiVNC MacOS Package
           path: build/*.dmg
       - name: Archive Windows Build Artifacts
         if: ${{ matrix.os == 'windows-latest' }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: MultiVNC Windows Package
           path: build/*.exe