Bump coverlet.msbuild from 6.0.2 to 6.0.3 (#237)

Bumps [coverlet.msbuild](https://github.com/coverlet-coverage/coverlet) from 6.0.2 to 6.0.3.
- [Release notes](https://github.com/coverlet-coverage/coverlet/releases)
- [Commits](coverlet-coverage/coverlet@v6.0.2...v6.0.3)

---
updated-dependencies:
- dependency-name: coverlet.msbuild
  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>

Author: dependabot[bot]

test/Serilog.Sinks.Splunk.TCP.Tests/Serilog.Sinks.Splunk.TCP.Tests.csproj

@@ -20,7 +20,7 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="coverlet.msbuild" Version="6.0.2">
+    <PackageReference Include="coverlet.msbuild" Version="6.0.3">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>

test/Serilog.Sinks.Splunk.Tests/Serilog.Sinks.Splunk.Tests.csproj

@@ -19,7 +19,7 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="coverlet.msbuild" Version="6.0.2">
+    <PackageReference Include="coverlet.msbuild" Version="6.0.3">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>