Bump ppy.osu.Game from 2026.605.0 to 2026.621.0

---
updated-dependencies:
- dependency-name: ppy.osu.Game
  dependency-version: 2026.621.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

osu.Game.Rulesets.Sentakki/osu.Game.Rulesets.Sentakki.csproj

@@ -9,7 +9,7 @@
         <AssemblyName>osu.Game.Rulesets.Sentakki</AssemblyName>
     </PropertyGroup>
     <ItemGroup>
-        <PackageReference Include="ppy.osu.Game" Version="2026.605.0" />
+        <PackageReference Include="ppy.osu.Game" Version="2026.621.0" />
     </ItemGroup>
 
     <!--Since we aren't changing the assembly name, we use the assembly title to indicate whether it is a dev build-->