Some fixes in the rendering of the Toolkit tutorials (#2800)

* fix mdoc converter

* Fix links

Author: adpi2

_overviews/toolkit/http-client-json.md

@@ -125,4 +125,4 @@ Running the program should print your own login.
 ## Sending and receiving Scala objects using JSON
 
 Alternatively, you can use uPickle to send or receive Scala objects using JSON.
-Read the following to learn [*How to serialize an object to JSON*](/toolkit/json-serialize) and [*How to deserialize JSON to an object*](/toolkit/json-deserialize).
+Read the following to learn [*How to serialize an object to JSON*](/toolkit/json-serialize.html) and [*How to deserialize JSON to an object*](/toolkit/json-deserialize.html).

_overviews/toolkit/json-files.md

@@ -69,4 +69,4 @@ os.write(os.pwd / "pet-owner-updated.json", write(petOwnerUpdated))
 {% endtabs %}
 
 To serialize and deserialize Scala case classes (or enums) to JSON we need an instance of `ReadWriter`.
-To understand how uPickle generates it for you, you can read the [*How to deserialize JSON to an object?*](/toolkit/json-deserialize) or the [*How to serialize an object to JSON?*](/toolkit/json-serialize) tutorials.
+To understand how uPickle generates it for you, you can read the [*How to deserialize JSON to an object?*](/toolkit/json-deserialize.html) or the [*How to serialize an object to JSON?*](/toolkit/json-serialize.html) tutorials.

_plugins/mdoc_replace.rb

@@ -16,6 +16,7 @@ def convert(content)
       content = content.gsub("```scala mdoc:fail\n", "```scala\n")
       content = content.gsub("```scala mdoc:crash\n", "```scala\n")
       content = content.gsub("```scala mdoc:nest\n", "```scala\n")
+      content = content.gsub("```scala mdoc:reset:crash\n", "```scala\n")
       content = content.gsub("```scala mdoc:reset\n", "```scala\n")
       content.gsub("```scala mdoc\n", "```scala\n")
     end