chore: bump ecdsa-dotnet version (#1100)

Author: JenniferMah

src/SendGrid/SendGrid.csproj

@@ -42,7 +42,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0" PrivateAssets="All" Condition=" '$(OS)' != 'Windows_NT' " />
     <PackageReference Include="Newtonsoft.Json" Version="9.0.1" />
-    <PackageReference Include="starkbank-ecdsa" Version="[1.2.0, 2.0.0)" />
+    <PackageReference Include="starkbank-ecdsa" Version="[1.3.1, 2.0.0)" />
   </ItemGroup>
 
   <ItemGroup Condition=" '$(TargetFramework)' == 'net452' ">