Bump the speckle group in /packages/converters with 2 updates

Bumps the speckle group in /packages/converters with 2 updates: [Speckle.Objects](https://github.com/specklesystems/speckle-sharp) and [Speckle.Objects.Converter.Grasshopper7](https://github.com/specklesystems/speckle-sharp).


Updates `Speckle.Objects` from 2.14.2 to 2.15.3
- [Release notes](https://github.com/specklesystems/speckle-sharp/releases)
- [Commits](specklesystems/speckle-sharp@2.14.2...nugets/2.15.3)

Updates `Speckle.Objects.Converter.Grasshopper7` from 2.14.2 to 2.15.3
- [Release notes](https://github.com/specklesystems/speckle-sharp/releases)
- [Commits](specklesystems/speckle-sharp@2.14.2...nugets/2.15.3)

---
updated-dependencies:
- dependency-name: Speckle.Objects
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: speckle
- dependency-name: Speckle.Objects.Converter.Grasshopper7
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: speckle
...

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

packages/converters/Nodepen.Converters.csproj

@@ -12,8 +12,8 @@
 
   <ItemGroup>
     <!-- <PackageReference Include="Rhino.Inside" Version="7.0.0" /> -->
-    <PackageReference Include="Speckle.Objects" Version="2.14.2" />
-    <PackageReference Include="Speckle.Objects.Converter.Grasshopper7" Version="2.14.2" />
+    <PackageReference Include="Speckle.Objects" Version="2.15.3" />
+    <PackageReference Include="Speckle.Objects.Converter.Grasshopper7" Version="2.15.3" />
   </ItemGroup>
 
 </Project>