fix: codec definition

ticket: WP-6702

TICKET: WP-6702

Author: danielzhao122

modules/express/openapi-generator.rc.js

@@ -14,7 +14,7 @@ module.exports = (E) => {
       NonEmptyString: () => E.right({ type: 'string', minLength: 1 }),
       DateFromISOString: () => E.right({ type: 'string', format: 'date-time' }),
       BigIntFromString: () => E.right({ type: 'string' }),
-      BooleanFromString: () => E.right({ type: 'string', enum: ['true', 'false'] }),
+      BooleanFromString: () => E.right({ type: 'boolean' }),
     },
     'io-ts-bigint': {
       BigIntFromString: () => E.right({ type: 'string' }),