Fix(request) retries is broken (#1005)

At the moment, when the method `shouldRetryCondition` is called, the condition are using OR which does not take in count 0 which is also considered as false
a simple fix is the usage of nullish coalescing

packages/medusa-js/src/request.ts

@@ -159,8 +159,8 @@ class Client {
         if (cfg) {
           return this.shouldRetryCondition(
             err,
-            cfg.currentRetryAttempt || 1,
-            cfg.retry || 3
+            cfg.currentRetryAttempt ?? 1,
+            cfg.retry ?? 3
           )
         } else {
           return false