Merge pull request #8016 from zalando-incubator/use-bigger-instance-e2e

[e2e] use bigger instance for `default-worker-splitaz` to avoid flake

Author: linki

test/e2e/cluster_config.sh

@@ -62,7 +62,7 @@ clusters:
     max_size: 2
   - discount_strategy: none
     instance_types:
-    - "m6i.xlarge"
+    - "m6i.2xlarge"
     name: default-worker-splitaz
     profile: worker-splitaz
     min_size: 0