minor correction for type comments (#3052)

'yes' and 'no' are no longer default conversions for boolean

Author: jenni-okelly

lib/index.d.ts

@@ -2118,12 +2118,12 @@ declare namespace Joi {
         array<TSchema = any[]>(): ArraySchema<TSchema>;
 
         /**
-         * Generates a schema object that matches a boolean data type (as well as the strings 'true', 'false', 'yes', and 'no'). Can also be called via boolean().
+         * Generates a schema object that matches a boolean data type (as well as the strings 'true' and 'false'). Can also be called via boolean().
          */
         bool<TSchema = boolean>(): BooleanSchema<TSchema>;
 
         /**
-         * Generates a schema object that matches a boolean data type (as well as the strings 'true', 'false', 'yes', and 'no'). Can also be called via bool().
+         * Generates a schema object that matches a boolean data type (as well as the strings 'true' and 'false'). Can also be called via bool().
          */
         boolean<TSchema = boolean>(): BooleanSchema<TSchema>;