build(deps): bump actions/{download,upload}-artifact from 3 to 4

originally #3058 and #3059, but I reverted those commits because the
artifact infrastructure was [flaky][] when first released. It seems
more stable now, so trying again.

- [flaky] actions/download-artifact#249

.github/workflows/ci.yml

@@ -440,7 +440,7 @@ jobs:
           docker run --rm -v "$(pwd):/nokogiri" -w /nokogiri \
             ${DOCKER_IMAGE} \
             ./scripts/test-gem-build gems ruby
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: generic-gem
           path: gems
@@ -462,7 +462,7 @@ jobs:
         with:
           ruby-version: "${{matrix.ruby}}"
           apt-get: "libxml2-dev libxslt1-dev pkg-config"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: generic-gem
           path: gems
@@ -483,7 +483,7 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: "${{matrix.ruby}}"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: generic-gem
           path: gems
@@ -505,7 +505,7 @@ jobs:
         with:
           ruby-version: "${{matrix.ruby}}"
           mingw: "libxml2 libxslt"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: generic-gem
           path: gems
@@ -528,7 +528,7 @@ jobs:
         with:
           ruby-version: "${{matrix.ruby}}"
           mingw: "libxml2 libxslt"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: generic-gem
           path: gems
@@ -566,7 +566,7 @@ jobs:
           docker run --rm -v "$(pwd):/nokogiri" -w /nokogiri \
             ${DOCKER_IMAGE} \
             ./scripts/test-gem-build gems ${{matrix.plat}}
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: "cruby-${{matrix.plat}}-gem"
           path: gems
@@ -583,7 +583,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           submodules: true
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-x86-linux-gem
           path: gems
@@ -605,7 +605,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           submodules: true
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-aarch64-linux-gem
           path: gems
@@ -627,7 +627,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           submodules: true
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-arm-linux-gem
           path: gems
@@ -652,7 +652,7 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: "${{matrix.ruby}}"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-x86_64-linux-gem
           path: gems
@@ -669,7 +669,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           submodules: true
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-x86_64-linux-gem
           path: gems
@@ -689,7 +689,7 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: "${{matrix.ruby}}"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-x86_64-darwin-gem
           path: gems
@@ -709,7 +709,7 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: "${{matrix.ruby}}"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-x64-mingw32-gem
           path: gems
@@ -730,7 +730,7 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: "${{matrix.ruby}}"
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: cruby-x64-mingw-ucrt-gem
           path: gems
@@ -747,7 +747,7 @@ jobs:
         with:
           submodules: true
       - run: ./scripts/test-gem-build gems java
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: jruby-gem
           path: gems
@@ -766,7 +766,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           submodules: true
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: jruby-gem
           path: gems