fix: The data.aws_ami.eks_default filter requires sting and got null

[aidanmelen]

Description

The data.aws_ami.eks_default filter requires sting and get null by default.

Motivation and Context

#1959 (comment)

Breaking Changes

N/A

How Has This Been Tested?

• comment out the cluster_version in the self_managed_node_group_example and let it default to null
• run a plan

╷
│ Error: Invalid template interpolation value
│ 
│   on ../../modules/self-managed-node-group/main.tf line 10, in data "aws_ami" "eks_default":
│   10:     values = ["amazon-eks-node-${var.cluster_version}-v*"]
│     ├────────────────
│     │ var.cluster_version is null
│ 
│ The expression result is null. Cannot include a null value in a string template.
╵
╷
│ Error: Invalid template interpolation value
│ 
│   on ../../modules/self-managed-node-group/main.tf line 10, in data "aws_ami" "eks_default":
│   10:     values = ["amazon-eks-node-${var.cluster_version}-v*"]
│     ├────────────────
│     │ var.cluster_version is null
│ 
│ The expression result is null. Cannot include a null value in a string template.
╵
╷
│ Error: Invalid template interpolation value
│ 
│   on ../../modules/self-managed-node-group/main.tf line 10, in data "aws_ami" "eks_default":
│   10:     values = ["amazon-eks-node-${var.cluster_version}-v*"]
│     ├────────────────
│     │ var.cluster_version is null
│ 
│ The expression result is null. Cannot include a null value in a string template.
╵
╷
│ Error: Invalid template interpolation value
│ 
│   on ../../modules/self-managed-node-group/main.tf line 10, in data "aws_ami" "eks_default":
│   10:     values = ["amazon-eks-node-${var.cluster_version}-v*"]
│     ├────────────────
│     │ var.cluster_version is null
│ 
│ The expression result is null. Cannot include a null value in a string template.
╵

[antonbabenko]

This issue has been resolved in version 18.14.1 🎉

[github-actions]

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