build: add extra test for Node 20, update windows tests (#1468)

* build: add extra test for Node 20, update windows tests

Source-Link: googleapis/synthtool@38f5d4b
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-nodejs:latest@sha256:ef104a520c849ffde60495342ecf099dfb6256eab0fbd173228f447bc73d1aa9

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: sofisl <[email protected]>

Author: gcf-owl-bot[bot]

.github/.OwlBot.lock.yaml

@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-nodejs:latest
-  digest: sha256:0527a86c10b67742c409dc726ba9a31ec4e69b0006e3d7a49b0e6686c59cdaa9
-# created: 2023-05-24T20:32:43.844586914Z
+  digest: sha256:ef104a520c849ffde60495342ecf099dfb6256eab0fbd173228f447bc73d1aa9
+# created: 2023-07-10T21:36:52.433664553Z