Fixing #i rendering

On the docs page, the letter `i` is not rendered for nuget source snippets. This might be because the language is set to `fsharp`. 

The NuGet installation snippets don't have `fsharp` as the language of the code snippet and the letter `r` renders correctly. This is a quick fix and might need more investigation on the F# Formatting side.

Author: luisquintanilla

docs/index.fsx

@@ -100,7 +100,7 @@ If the interactive extension does not work, please file an issue and we will try
 
 A possible fix for this is the inclusion of Dotnet.Interactive preview package sources. To use these, add the following lines before referencning Plotly.NET.Interactive:
 
-```fsharp
+```
 #i "nuget:https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet5/nuget/v3/index.json"
 #i "nuget:https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3/index.json"
 ```