Bump System.Runtime.CompilerServices.Unsafe and System.Threading.Task…

…s.Extensions

Bumps [System.Runtime.CompilerServices.Unsafe](https://github.com/dotnet/maintenance-packages) and [System.Threading.Tasks.Extensions](https://github.com/dotnet/maintenance-packages). These dependencies needed to be updated together.

Updates `System.Runtime.CompilerServices.Unsafe` from 6.0.0 to 6.1.0
- [Release notes](https://github.com/dotnet/maintenance-packages/releases)
- [Commits](https://github.com/dotnet/maintenance-packages/commits)

Updates `System.Threading.Tasks.Extensions` from 4.5.4 to 4.6.0
- [Release notes](https://github.com/dotnet/maintenance-packages/releases)
- [Commits](https://github.com/dotnet/maintenance-packages/commits)

---
updated-dependencies:
- dependency-name: System.Runtime.CompilerServices.Unsafe
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: System.Threading.Tasks.Extensions
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

MailKit/MailKit.csproj

@@ -52,11 +52,11 @@
 
   <ItemGroup Condition=" $(TargetFramework.StartsWith('net4')) Or '$(TargetFramework)' == 'netstandard2.0' ">
     <PackageReference Include="System.Formats.Asn1" Version="8.0.1" />
-    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.4" />
+    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.6.0" />
   </ItemGroup>
 
   <ItemGroup Condition=" $(TargetFramework.StartsWith('net4')) Or $(TargetFramework.StartsWith('netstandard2.')) ">
-    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="6.0.0" />
+    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="6.1.0" />
   </ItemGroup>
 
   <ItemGroup>

MailKit/MailKitLite.csproj

@@ -53,15 +53,15 @@
 
   <ItemGroup Condition=" $(TargetFramework.StartsWith('net4')) Or '$(TargetFramework)' == 'netstandard2.0' ">
     <PackageReference Include="System.Formats.Asn1" Version="8.0.1" />
-    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.4" />
+    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.6.0" />
   </ItemGroup>
 
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' ">
     <PackageReference Include="System.Formats.Asn1" Version="8.0.1" />
   </ItemGroup>
 
   <ItemGroup Condition=" $(TargetFramework.StartsWith('net4')) Or $(TargetFramework.StartsWith('netstandard2.')) ">
-    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="6.0.0" />
+    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="6.1.0" />
   </ItemGroup>
 
   <ItemGroup>