Bump Microsoft.NET.Sdk.Functions (#257)

Bumps [Microsoft.NET.Sdk.Functions](https://github.com/Azure/azure-functions-vs-build-sdk) from 3.1.0 to 3.1.2.
- [Release notes](https://github.com/Azure/azure-functions-vs-build-sdk/releases)
- [Commits](https://github.com/Azure/azure-functions-vs-build-sdk/commits)

---
updated-dependencies:
- dependency-name: Microsoft.NET.Sdk.Functions
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Marc Duiker <[email protected]>

Author: dependabot[bot]

src/dotnetcore31/AzureFunctions.Blob/AzureFunctions.Blob.csproj

@@ -5,7 +5,7 @@
     <RootNamespace>AzureFunctions.Blob</RootNamespace>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Sdk.Functions" Version="3.1.0"/>
+    <PackageReference Include="Microsoft.NET.Sdk.Functions" Version="3.1.2"/>
     <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.Storage" Version="4.0.5"/>
     <PackageReference Include="Azure.Storage.Blobs" Version="12.13.1"/>
   </ItemGroup>