Fix sample's readme (#1499)

Youssef1313 · Ron Petrusha · commit 1009617d2c9a · 2019-09-19T15:14:31.000Z
diff --git a/async/async-and-await/vb/readme.md b/async/async-and-await/vb/readme.md
@@ -1,7 +1,7 @@
 ---
 languages:
 - vb
- products:
+products:
 - dotnet-core
 - windows
 page_type: sample
