Update update-example-builder.yml

Update Go version.

.github/workflows/update-example-builder.yml

@@ -18,7 +18,7 @@ jobs:
                 username: ${{ secrets.PAKETO_BUILDPACKS_DOCKERHUB_USERNAME }}
             - uses: actions/setup-go@v5
               with:
-                go-version: "1.18"
+                go-version: "1.20"
             - name: Install update-package-dependency
               run: |
                 #!/usr/bin/env bash