Bump Polly from 8.3.1 to 8.4.0

Bumps [Polly](https://github.com/App-vNext/Polly) from 8.3.1 to 8.4.0.
- [Release notes](https://github.com/App-vNext/Polly/releases)
- [Changelog](https://github.com/App-vNext/Polly/blob/main/CHANGELOG.md)
- [Commits](App-vNext/Polly@8.3.1...8.4.0)

---
updated-dependencies:
- dependency-name: Polly
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

build/_build.csproj

@@ -11,7 +11,7 @@
 
   <ItemGroup>
     <PackageReference Include="Nuke.Common" Version="8.0.0" />
-    <PackageReference Include="Polly" Version="8.3.1" />
+    <PackageReference Include="Polly" Version="8.4.0" />
   </ItemGroup>
 
   <ItemGroup>