Bump MahApps.Metro.IconPacks from 5.1.0 to 6.1.0

---
updated-dependencies:
- dependency-name: MahApps.Metro.IconPacks
  dependency-version: 6.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

DBison.WPF/DBison.WPF.csproj

@@ -35,7 +35,7 @@
 
   <ItemGroup>
     <PackageReference Include="MahApps.Metro" Version="2.4.10" />
-    <PackageReference Include="MahApps.Metro.IconPacks" Version="5.1.0" />
+    <PackageReference Include="MahApps.Metro.IconPacks" Version="6.1.0" />
   </ItemGroup>
 
   <ItemGroup>