test(request): let last character always be a new line as supported by all sequential media types

Author: Fresa

tests/Example.OpenApi32.IntegrationTests/ImportFooEventsTests.cs

@@ -24,6 +24,7 @@ public async Task ImportingFooEvents_ShouldReturnAccepted(string mediaType, stri
                 $$"""
                 {{prefix}}{ "Name": "test" }
                 {{prefix}}{ "Name": "another test" }
+                
                 """, mediaType)
         }, CancellationToken);