fix line endings

Author: SimonCropp

src/Directory.Build.props

@@ -2,7 +2,7 @@
 <Project>
   <PropertyGroup>
     <NoWarn>CS1591;CS0649;CA1416;NU1608;NU1109</NoWarn>
-    <Version>0.2.0</Version>
+    <Version>0.2.1</Version>
     <LangVersion>preview</LangVersion>
     <AssemblyVersion>1.0.0</AssemblyVersion>
     <PackageTags>ClosedXML, Excel, Verify</PackageTags>

src/Verify.ClosedXml/VerifyClosedXml.cs

@@ -116,7 +116,7 @@ static ConversionResult Convert(XLWorkbook book, IReadOnlyDictionary<string, obj
                 }
 
                 builder.Length -= 1;
-                builder.AppendLine();
+                builder.AppendLineN();
             }
 
             yield return (builder, sheet.Name);