Fix typo in doc for Aws::InstanceProfileCredentials#disable_imds_v1 (#3316)

Author: ybiquitous

gems/aws-sdk-core/lib/aws-sdk-core/instance_profile_credentials.rb

@@ -95,7 +95,7 @@ def initialize(options = {})
       super
     end
 
-    # @return [Boolean0
+    # @return [Boolean]
     attr_reader :disable_imds_v1
 
     # @return [Integer]