Add support for allow/deny regexp(s) in instanceSelector

[dims]

xref: #3718

It is useful to have expose allow and deny functionality already in ec2-instance-selector as i don't see any other helpful feature/future suggestions in #3718 are happening anytime soon.

Tested with the following config by hand in addition to the test case:

apiVersion: eksctl.io/v1alpha5
kind: ClusterConfig
metadata:
  name: your-cluster-name
  region: us-west-2

managedNodeGroups:
  - name: worker-1c-spot-2-v5
    minSize: 0
    maxSize: 60
    privateNetworking: true
    labels:
      unimed.de/nodegroup: worker
    amiFamily: Bottlerocket
    iam:
      withAddonPolicies:
        autoScaler: true
        efs: true
        ebs: true
        cloudWatch: true
    taints:
      - key: nodegroup
        value: worker
        effect: NoSchedule
    propagateASGTags: true
    instanceSelector:
      vCPUs: 8
      memory: 16GiB
      cpuArchitecture: x86_64

without any allow/deny statements you will see following instanceTypes:

  instanceTypes:
  - c5.2xlarge
  - c5a.2xlarge
  - c5d.2xlarge
  - c6a.2xlarge
  - c6i.2xlarge
  - c6id.2xlarge
  - c6in.2xlarge
  - c7a.2xlarge
  - c7i-flex.2xlarge
  - c7i.2xlarge
  - inf1.2xlarge

then added various combinations of allow and deny to make sure the list of instance types matches what is expected.

example:

allow : "c5[a-d]+.*"

deny : "inf1.*"

[dims]

cc @bryantbiggs