Update cache action to v4 (apache#6744)

- consistent with other usages of `actions/cache` in workflows
- addresses a warning raised by GitHub:
  ```
  Verify MSRV
  The following actions use a deprecated Node.js version and will be
  forced to run on node20: actions/cache@v3.
  ```

.github/actions/setup-builder/action.yaml

@@ -30,7 +30,7 @@ runs:
   using: "composite"
   steps:
     - name: Cache Cargo
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         # these represent dependencies downloaded by cargo
         # and thus do not depend on the OS, arch nor rust version.