eventbridge-schedule-to-ec2-terraform: Fix "Most Recent Image Not Filtered" error

[kakakakakku]

Issue #, if available:
N/A

Description of changes:
Hi😀 Thanks for the useful patterns!

While testing eventbridge-schedule-to-ec2-terraform, I occurred Most Recent Image Not Filtered error. And more I noticed that the managed_policy_arns argument is already deprecated.

╷
│ Error: Most Recent Image Not Filtered
│ 
│   with data.aws_ami.amazon-linux-2,
│   on main.tf line 35, in data "aws_ami" "amazon-linux-2":
│   35: data "aws_ami" "amazon-linux-2" {
│ 
│ "most_recent" is set to "true" and results are not filtered by owner or image ID. With this configuration, a third party may introduce a new image which will be returned by this data source. Filter by owner or image
│ ID to avoid this possibility.
╵

"managed_policy_arns" is deprecated

Check

terraform apply completed successfully and it works good with updating cron schedule for quick testing.

Thank you😀

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[kakakakakku]

note: The managed_policy_arns argument is already deprecated. I update code correctly😀 See document below.

• https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/iam_role

[kakakakakku]

https://registry.terraform.io/providers/hashicorp/aws/latest/docs/data-sources/ami