Update 1 NuGet dependencies

Author: github-actions[bot]

nanoFramework.SignalR.Client.nuspec

@@ -19,7 +19,7 @@
     <tags>nanoFramework C# csharp netmf netnf SignalR</tags>
     <dependencies>
       <dependency id="nanoFramework.CoreLibrary" version="1.12.0-preview.9" />
-      <dependency id="nanoFramework.Json" version="2.1.2-preview.50" />
+      <dependency id="nanoFramework.Json" version="2.1.2-preview.52" />
       <dependency id="nanoFramework.Runtime.Events" version="1.10.0-preview.8" />
       <dependency id="nanoFramework.System.Collections" version="1.4.0-preview.7" />
       <dependency id="nanoFramework.System.Net" version="1.8.0-preview.29" />

nanoFramework.SignalR.Client/nanoFramework.SignalR.Client.nfproj

@@ -48,15 +48,15 @@
       <Private>True</Private>
     </Reference>
     <Reference Include="nanoFramework.Json, Version=2.1.2.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\packages\nanoFramework.Json.2.1.2-preview.50\lib\nanoFramework.Json.dll</HintPath>
+      <HintPath>..\packages\nanoFramework.Json.2.1.2-preview.52\lib\nanoFramework.Json.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="nanoFramework.Runtime.Events, Version=1.10.0.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
       <HintPath>..\packages\nanoFramework.Runtime.Events.1.10.0-preview.8\lib\nanoFramework.Runtime.Events.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="nanoFramework.System.Collections, Version=1.4.0.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\packages\nanoFramework.System.Collections.1.4.0-preview.16\lib\nanoFramework.System.Collections.dll</HintPath>
+      <HintPath>..\packages\nanoFramework.System.Collections.1.4.0-preview.21\lib\nanoFramework.System.Collections.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="nanoFramework.System.Text, Version=1.1.3.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">

nanoFramework.SignalR.Client/packages.config

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="nanoFramework.CoreLibrary" version="1.12.0-preview.9" targetFramework="netnanoframework10" />
-  <package id="nanoFramework.Json" version="2.1.2-preview.50" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.Json" version="2.1.2-preview.52" targetFramework="netnanoframework10" />
   <package id="nanoFramework.Runtime.Events" version="1.10.0-preview.8" targetFramework="netnanoframework10" />
-  <package id="nanoFramework.System.Collections" version="1.4.0-preview.16" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.System.Collections" version="1.4.0-preview.21" targetFramework="netnanoframework10" />
   <package id="nanoFramework.System.IO.Streams" version="1.0.0-preview.12" />
   <package id="nanoFramework.System.Net" version="1.8.0-preview.29" targetFramework="netnanoframework10" />
   <package id="nanoFramework.System.Net.WebSockets.Client" version="1.0.0-preview.85" targetFramework="netnanoframework10" />