Bump MailKit from 4.6.0 to 4.7.0 (#549)

Bumps [MailKit](https://github.com/jstedfast/MailKit) from 4.6.0 to
4.7.0.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/jstedfast/MailKit/blob/master/ReleaseNotes.md">MailKit's
changelog</a>.</em></p>
<blockquote>
<h1>Release Notes</h1>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li>See full diff in <a
href="https://github.com/jstedfast/MailKit/commits">compare
view</a></li>
</ul>
</details>
<br />


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</details>

Refresh.GameServer/Refresh.GameServer.csproj

@@ -68,7 +68,7 @@
       <PackageReference Include="Discord.Net.Webhook" Version="3.15.2" />
       <PackageReference Include="FastAes" Version="1.0.1" />
       <PackageReference Include="IronCompress" Version="1.5.2" />
-      <PackageReference Include="MailKit" Version="4.6.0" />
+      <PackageReference Include="MailKit" Version="4.7.0" />
       <PackageReference Include="NPTicket" Version="3.1.0" />
       <PackageReference Include="Pfim" Version="0.11.2" />
       <PackageReference Include="Realm" Version="12.2.0" />