Added the jq requirement note

the plan file needs to be pretty printed in order to see the issue in the code block. If the plan file is in raw json then the code block doesn't appear. This isn't obvious in the documentation. I added a note.

docs/2.Basics/Installing Checkov.md

@@ -86,7 +86,7 @@ check: CKV_AWS_21: "Ensure all data stored in the S3 bucket have versioning enab
 	Guide: https://docs.prismacloud.io/en/enterprise-edition/policy-reference/aws-policies/s3-policies/s3-16-enable-versioning
 ```
 
-If you have installed jq, you can convert a JSON file into multiple lines with the command `terraform show -json tf.plan | jq '.' > tf.json`, making it easier to read the scan result.
+If you have installed jq, you can convert a JSON file into multiple lines with the command `terraform show -json tf.plan | jq '.' > tf.json`, making it easier to read the scan result. NOTE: `jq` is required to show the code block as seen below. 
 
 ```json
 checkov -f tf.json