chore(aws-eks): changed instanceType to instanceTypes in addNodegroup…

…Capacity functions (#22590)

fixes #22547 

---
 
Since `instanceType` is deprecated, I changed it to `instanceTypes` in all the `addNodegroupCapacity` functions

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packages/@aws-cdk/aws-eks/test/integ.eks-cluster.ts

@@ -192,7 +192,7 @@ class EksClusterStack extends Stack {
   private assertNodeGroupX86() {
     // add a extra nodegroup
     this.cluster.addNodegroupCapacity('extra-ng', {
-      instanceType: new ec2.InstanceType('t3.small'),
+      instanceTypes: [new ec2.InstanceType('t3.small')],
       minSize: 1,
       // reusing the default capacity nodegroup instance role when available
       nodeRole: this.cluster.defaultCapacity ? this.cluster.defaultCapacity.role : undefined,
@@ -241,7 +241,7 @@ class EksClusterStack extends Stack {
   private assertNodeGroupArm() {
     // add a extra nodegroup
     this.cluster.addNodegroupCapacity('extra-ng-arm', {
-      instanceType: new ec2.InstanceType('m6g.medium'),
+      instanceTypes: [new ec2.InstanceType('m6g.medium')],
       minSize: 1,
       // reusing the default capacity nodegroup instance role when available
       nodeRole: this.cluster.defaultCapacity ? this.cluster.defaultCapacity.role : undefined,
@@ -250,7 +250,7 @@ class EksClusterStack extends Stack {
   private assertNodeGroupGraviton3() {
     // add a Graviton3 nodegroup
     this.cluster.addNodegroupCapacity('extra-ng-arm3', {
-      instanceType: new ec2.InstanceType('c7g.large'),
+      instanceTypes: [new ec2.InstanceType('c7g.large')],
       minSize: 1,
       // reusing the default capacity nodegroup instance role when available
       nodeRole: this.cluster.defaultCapacity ? this.cluster.defaultCapacity.role : undefined,