Bump Polly from 8.3.1 to 8.4.0 (#478)

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

src/ModularPipelines/ModularPipelines.csproj

@@ -50,7 +50,7 @@
 
     <ItemGroup>
       <PackageReference Include="CliWrap" Version="3.6.6" />
-      <PackageReference Include="Polly" Version="8.3.1" />
+      <PackageReference Include="Polly" Version="8.4.0" />
       <PackageReference Include="Spectre.Console" Version="0.49.1" />
       <PackageReference Include="System.Text.Json" Version="8.0.3" />
       <PackageReference Include="EnumerableAsyncProcessor" Version="1.3.2" />