ci: update {download,upload}-artifact Action versions

Bumps `actions/upload-artifact` from 4 to 5.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/v4...v5)

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

Originally-authored-by: dependabot[bot] <support@github.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index aa6bce6..46203d3 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -123,7 +123,7 @@
     - name: zip up tracked files
       run: git archive -o artifacts/tracked.tar.gz HEAD
     - name: upload tracked files and build artifacts
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: windows-artifacts
         path: artifacts
@@ -140,7 +140,7 @@
       cancel-in-progress: ${{ needs.ci-config.outputs.skip_concurrent == 'yes' }}
     steps:
     - name: download tracked files and build artifacts
-      uses: actions/download-artifact@v5
+      uses: actions/download-artifact@v6
       with:
         name: windows-artifacts
         path: ${{github.workspace}}
@@ -157,7 +157,7 @@
       run: ci/print-test-failures.sh
     - name: Upload failed tests' directories
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: failed-tests-windows-${{ matrix.nr }}
         path: ${{env.FAILED_TEST_ARTIFACTS}}
@@ -208,7 +208,7 @@
     - name: zip up tracked files
       run: git archive -o artifacts/tracked.tar.gz HEAD
     - name: upload tracked files and build artifacts
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: vs-artifacts
         path: artifacts
@@ -226,7 +226,7 @@
     steps:
     - uses: git-for-windows/setup-git-for-windows-sdk@v1
     - name: download tracked files and build artifacts
-      uses: actions/download-artifact@v5
+      uses: actions/download-artifact@v6
       with:
         name: vs-artifacts
         path: ${{github.workspace}}
@@ -244,7 +244,7 @@
       run: ci/print-test-failures.sh
     - name: Upload failed tests' directories
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: failed-tests-windows-vs-${{ matrix.nr }}
         path: ${{env.FAILED_TEST_ARTIFACTS}}
@@ -270,7 +270,7 @@
       shell: pwsh
       run: meson compile -C build
     - name: Upload build artifacts
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: windows-meson-artifacts
         path: build
@@ -292,7 +292,7 @@
       shell: pwsh
       run: pip install meson ninja
     - name: Download build artifacts
-      uses: actions/download-artifact@v5
+      uses: actions/download-artifact@v6
       with:
         name: windows-meson-artifacts
         path: build
@@ -339,7 +339,7 @@
       run: ci/print-test-failures.sh
     - name: Upload failed tests' directories
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: failed-tests-${{matrix.vector.jobname}}
         path: ${{env.FAILED_TEST_ARTIFACTS}}
@@ -439,7 +439,7 @@
       run: sudo --preserve-env --set-home --user=builder ci/print-test-failures.sh
     - name: Upload failed tests' directories
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: failed-tests-${{matrix.vector.jobname}}
         path: ${{env.FAILED_TEST_ARTIFACTS}}