Bump AkkaVersion from 1.5.12 to 1.5.13

Bumps `AkkaVersion` from 1.5.12 to 1.5.13.

Updates `Akka` from 1.5.12 to 1.5.13
- [Release notes](https://github.com/akkadotnet/akka.net/releases)
- [Changelog](https://github.com/akkadotnet/akka.net/blob/dev/RELEASE_NOTES.md)
- [Commits](akkadotnet/akka.net@1.5.12...1.5.13)

Updates `Akka.TestKit.Xunit2` from 1.5.12 to 1.5.13
- [Release notes](https://github.com/akkadotnet/akka.net/releases)
- [Changelog](https://github.com/akkadotnet/akka.net/blob/dev/RELEASE_NOTES.md)
- [Commits](akkadotnet/akka.net@1.5.12...1.5.13)

Updates `Akka.Hosting.TestKit` from 1.5.12 to 1.5.13
- [Release notes](https://github.com/akkadotnet/akka.net/releases)
- [Changelog](https://github.com/akkadotnet/akka.net/blob/dev/RELEASE_NOTES.md)
- [Commits](akkadotnet/akka.net@1.5.12...1.5.13)

---
updated-dependencies:
- dependency-name: Akka
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: Akka.TestKit.Xunit2
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: Akka.Hosting.TestKit
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

src/Directory.Packages.props

@@ -1,7 +1,7 @@
 <Project>
   <PropertyGroup>
     <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-    <AkkaVersion>1.5.12</AkkaVersion>
+    <AkkaVersion>1.5.13</AkkaVersion>
   </PropertyGroup>
 
   <!-- App dependencies -->