Bump MailKit from 4.3.0 to 4.5.0

Bumps [MailKit](https://github.com/jstedfast/MailKit) from 4.3.0 to 4.5.0.
- [Changelog](https://github.com/jstedfast/MailKit/blob/master/ReleaseNotes.md)
- [Commits](jstedfast/MailKit@4.3.0...4.5.0)

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

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

src/Connectors.Smtp/Connectors.Smtp.csproj

@@ -10,7 +10,7 @@
 
 	<ItemGroup>
 		<PackageReference Include="Handlebars.Net" Version="2.1.4" />
-		<PackageReference Include="MailKit" Version="4.3.0" />
+		<PackageReference Include="MailKit" Version="4.5.0" />
 		<PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="8.0.0" />
 		<PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="8.0.1" />
 	</ItemGroup>