Bump Microsoft.Build.Tasks.Core from 17.14.28 to 18.4.0

---
updated-dependencies:
- dependency-name: Microsoft.Build.Tasks.Core
  dependency-version: 18.4.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

Directory.Packages.props

@@ -19,6 +19,6 @@
 
     <ItemGroup>
         <PackageVersion Include="Microsoft.Build.Tasks.Core"
-                        Version="17.14.28" />
+                        Version="18.4.0" />
     </ItemGroup>
 </Project>