Bump actions/upload-artifact from 3 to 4

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 3 to 4.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v3...v4)

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

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

.github/workflows/kibot.yml

@@ -45,7 +45,7 @@ jobs:
             hasl_green_top.svg hasl_green_bottom.svg oshpark_afterdark_top.svg oshpark_afterdark_bottom.svg oshpark_purple_top.svg oshpark_purple_bottom.svg \
             board_black_top.svg board_black_bottom.svg autocad.dxf model.step openboardview.brd \
             kicad_3d_view_top kicad_3d_view_bottom kicad_3d_view_front kicad_3d_view_rear kicad_3d_view_right kicad_3d_view_left
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         if: ${{success()}}
         with:
           name: ${{ matrix.board }}

.github/workflows/pico-build.yml

@@ -59,7 +59,7 @@ jobs:
       run: PICO_SDK_PATH=$GITHUB_WORKSPACE/pico-sdk cmake --build . --config $BUILD_TYPE --parallel 4
 
     - name: Save artifact
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
         name: rp2040-dmxsun
         path: ${{github.workspace}}/build/*.uf2