chore: small fixes to DESIGN_GUIDELINES.md (#9534)

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DESIGN_GUIDELINES.md

@@ -9,9 +9,10 @@ the AWS Construct Library in order to ensure a consistent and integrated
 experience across the entire AWS surface area.
 
 As much as possible, the guidelines in this document are enforced using the
-**awslint** tool which reflects on the APIs and verifies that the APIs adhere to
-the guidelines. When a guideline is backed by a linter rule, the rule name will
-be referenced like this: _[awslint:resource-class-is-construct]_.
+[**awslint** tool](https://www.npmjs.com/package/awslint) which reflects on the
+APIs and verifies that the APIs adhere to the guidelines. When a guideline is
+backed by a linter rule, the rule name will be referenced like this:
+_[awslint:resource-class-is-construct]_.
 
 For the purpose of this document we will use "Foo" to denote the official name
 of the resource as defined in the AWS CloudFormation resource specification
@@ -147,9 +148,9 @@ behavior through interfaces and not through inheritance.
 Construct classes should extend only one of the following classes
 [_awslint:construct-inheritence_]:
 
-* The **Resource** class (if it represents an AWS resource) The **Construct**
-* class (if it represents an abstract component) The **XxxBase** class (which,
-* in turn extends **Resource**)
+* The **Resource** class (if it represents an AWS resource)
+* The **Construct** class (if it represents an abstract component)
+* The **XxxBase** class (which, in turn extends **Resource**)
 
 All constructs must define a static type check method called **isFoo** with the
 following implementation [_awslint:static-type-check_]: