Bump System.Net.Http from 4.3.3 to 4.3.4 in /sdk/src/Core (#193)

Bumps System.Net.Http from 4.3.3 to 4.3.4.

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

sdk/src/Core/AWSXRayRecorder.Core.csproj

@@ -42,7 +42,7 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
-    <PackageReference Include="System.Net.Http" Version="4.3.3" />
+    <PackageReference Include="System.Net.Http" Version="4.3.4" />
     <PackageReference Include="Microsoft.AspNetCore.Http" Version="2.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration" Version="2.0.0" />
   </ItemGroup>