Merge pull request #37836 from jldohmann/BZ1889247-pt3

BZ#1889247: change diskSizeGB to new recommendation

Author: codyhoag

modules/installation-gcp-config-yaml.adoc

@@ -48,7 +48,7 @@ controlPlane: <2> <3>
       - us-central1-c
       osDisk:
         diskType: pd-ssd
-        diskSizeGB: 256
+        diskSizeGB: 1024
         encryptionKey: <5>
           kmsKey:
             name: worker-key