Bump actions/download-artifact from 3 to 4 (#334)

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

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/check-supported-versions.yaml

@@ -81,7 +81,7 @@ jobs:
       - name: Check out code
         uses: actions/checkout@v4
       - name: Download build artifact
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           name: artifact
       - name: Run Ensures Script

.github/workflows/openapi-generator.yaml

@@ -93,7 +93,7 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Download openapi-generator-cli.jar artifact
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           name: openapi-generator-cli.jar
           path: modules/openapi-generator-cli/target
@@ -131,7 +131,7 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Download openapi-generator-cli.jar artifact
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           name: openapi-generator-cli.jar
           path: modules/openapi-generator-cli/target