Bump diff engine to version 18.1.0 (#1661)

* Bump DiffEngine to version 18.1.0

Updated the DiffEngine package version from 18.0.1 to 18.1.0 in Directory.Packages.props to use the latest features and fixes.

* Update Directory.Build.props

Author: SimonCropp

src/Directory.Build.props

@@ -2,7 +2,7 @@
 <Project>
   <PropertyGroup>
     <NoWarn>CA1822;CS1591;CS0649;xUnit1026;xUnit1013;CS1573;VerifyTestsProjectDir;VerifySetParameters;PolyFillTargetsForNuget;xUnit1051;NU1608;NU1109</NoWarn>
-    <Version>31.9.0</Version>
+    <Version>31.9.1</Version>
     <ImplicitUsings>enable</ImplicitUsings>
     <LangVersion>preview</LangVersion>
     <AssemblyVersion>1.0.0</AssemblyVersion>

src/Directory.Packages.props

@@ -7,7 +7,7 @@
     <PackageVersion Include="Argon" Version="0.33.0" />
     <PackageVersion Include="Argon.FSharp" Version="0.33.0" />
     <PackageVersion Include="BenchmarkDotNet" Version="0.15.8" />
-    <PackageVersion Include="DiffEngine" Version="18.0.1" />
+    <PackageVersion Include="DiffEngine" Version="18.1.0" />
     <PackageVersion Include="Expecto" Version="10.2.3" />
     <PackageVersion Include="Fixie" Version="4.2.0" />
     <PackageVersion Include="Fixie.TestAdapter" Version="4.2.0" />