chore: bump SDK to 1.6.20 (fixes Roslyn.Utilities 1.14.0 in package)

Author: ANcpLua

src/common/Version.props

@@ -16,7 +16,7 @@
       <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="$(RoslynVersion)"/>
   -->
   <PropertyGroup Label="SDK Version (Auto-generated)">
-    <ANcpSdkPackageVersion>1.6.19</ANcpSdkPackageVersion>
+    <ANcpSdkPackageVersion>1.6.20</ANcpSdkPackageVersion>
   </PropertyGroup>
 
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