fix: malformed policy document for sts assume role

[h1manshu98]

what

• Assume Role Policy statement

why

Current assume_role_policy is throwing below error

Error: creating IAM Role (aws-backup-ec2) : MalformedPolicyDocument: Has prohibited field Resource
status code: 400, request id: 12345678-abc-1234-1234-abcdegh with module.aws backup_ec2.aws_1am_role.default [0],
on .terraform/modules/aws backup ec2/main.tf line 101, in resource "aws iam role" "default":
101: resource "aws iam role" "default" {

[omsharma07]

LGTM