Update insomnia.md

Will not work if there's a space between the _.webapiurl and $metadata

Author: russrimm

powerapps-docs/developer/data-platform/webapi/insomnia.md

@@ -169,7 +169,7 @@ The Common Schema Definition Language (CSDL) $metadata document is the source of
 
 1. Edit the URL by appending `$metadata?annotations=true` after the `_.webapiurl` variable. The URL should be:
 
-   `GET _.webapiurl $metadata?annotations=true`
+   `GET _.webapiurl$metadata?annotations=true`
 
 1. Select **Send**.