Added "ec2:DeleteTags" to EC2 permissions table per BZ1926543

Author: GroceryBoyJr

modules/installation-aws-permissions.adoc

@@ -26,6 +26,7 @@ cluster, the IAM user requires the following permissions:
 * `ec2:CreateVolume`
 * `ec2:DeleteSecurityGroup`
 * `ec2:DeleteSnapshot`
+* `ec2:DeleteTags`
 * `ec2:DeregisterImage`
 * `ec2:DescribeAccountAttributes`
 * `ec2:DescribeAddresses`
@@ -258,4 +259,4 @@ If you use an existing VPC, your account does not require these permissions to d
 ====
 * `ec2:DescribeInstanceTypeOfferings`
 * `servicequotas:ListAWSDefaultServiceQuotas`
-====
+====