Bump MediatR from 12.2.0 to 12.3.0

Bumps [MediatR](https://github.com/jbogard/MediatR) from 12.2.0 to 12.3.0.
- [Release notes](https://github.com/jbogard/MediatR/releases)
- [Commits](LuckyPennySoftware/MediatR@v12.2.0...v12.3.0)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Directory.Packages.props

@@ -81,7 +81,7 @@
     <PackageVersion Include="Automapper" Version="13.0.1" />
     <PackageVersion Include="Dapper" Version="2.1.35" />
     <PackageVersion Include="FluentValidation.AspNetCore" Version="11.3.0" />
-    <PackageVersion Include="MediatR" Version="12.2.0" />
+    <PackageVersion Include="MediatR" Version="12.3.0" />
     <PackageVersion Include="Microsoft.Web.LibraryManager.Build" Version="2.1.175" />
     <PackageVersion Include="Polly" Version="8.4.0" />
     <PackageVersion Include="Swashbuckle.AspNetCore" Version="6.6.1" />