Bump FluentDateTime from 2.1.0 to 3.0.0 (#7114)

Bumps [FluentDateTime](https://github.com/FluentDateTime/FluentDateTime) from 2.1.0 to 3.0.0.
- [Release notes](https://github.com/FluentDateTime/FluentDateTime/releases)
- [Commits](FluentDateTime/FluentDateTime@2.1.0...3.0.0)

---
updated-dependencies:
- dependency-name: FluentDateTime
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

src/core/Akka.Discovery.Tests/Akka.Discovery.Tests.csproj

@@ -7,7 +7,7 @@
 
   <ItemGroup>
     <PackageReference Include="FluentAssertions" Version="$(FluentAssertionsVersion)" />
-    <PackageReference Include="FluentDateTime" Version="2.1.0" />
+    <PackageReference Include="FluentDateTime" Version="3.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="$(TestSdkVersion)" />
     <PackageReference Include="xunit" Version="$(XunitVersion)" />
     <PackageReference Include="xunit.runner.visualstudio" Version="$(XunitVersion)" />