Add allowDots config option for qs stringify (#20687)

types/qs/index.d.ts

@@ -5,6 +5,7 @@
 //                 Belinda Teh <https://github.com/tehbelinda>
 //                 Melvin Lee <https://github.com/zyml>
 //                 Arturs Vonda <https://github.com/artursvonda>
+//                 Carlos Bonetti <https://github.com/CarlosBonetti>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
 export = QueryString;
@@ -25,6 +26,7 @@ declare namespace QueryString {
         format?: 'RFC1738' | 'RFC3986';
         encodeValuesOnly?: boolean;
         addQueryPrefix?: boolean;
+        allowDots?: boolean;
     }
 
     interface IParseOptions {

types/qs/qs-tests.ts

@@ -287,3 +287,7 @@ qs.parse('a=b&c=d', { delimiter: '&' });
 () => {
     assert.equal(qs.stringify({ a: 'b' }, { addQueryPrefix: true }), '?a=b');
 }
+
+() => {
+    assert.equal(qs.stringify({ a: { b: { c: 'd', e: 'f' } } }, { allowDots: true }), 'a.b.c=d&a.b.e=f');
+}