Update 1 NuGet dependencies

Author: github-actions[bot]

source/TestFramework/nanoFramework.TestFramework.nfproj

@@ -40,7 +40,7 @@
   </ItemGroup>
   <ItemGroup>
     <Reference Include="mscorlib, Version=1.12.0.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\..\packages\nanoFramework.CoreLibrary.1.12.0-preview.18\lib\mscorlib.dll</HintPath>
+      <HintPath>..\..\packages\nanoFramework.CoreLibrary.1.12.0-preview.19\lib\mscorlib.dll</HintPath>
       <Private>True</Private>
     </Reference>
   </ItemGroup>

source/TestFramework/packages.config

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="nanoFramework.CoreLibrary" version="1.12.0-preview.18" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.CoreLibrary" version="1.12.0-preview.19" targetFramework="netnanoframework10" />
   <package id="Nerdbank.GitVersioning" version="3.4.255" developmentDependency="true" targetFramework="netnanoframework10" />
 </packages>

source/UnitTestLauncher/nanoFramework.UnitTestLauncher.nfproj

@@ -39,7 +39,7 @@
   </ItemGroup>
   <ItemGroup>
     <Reference Include="mscorlib, Version=1.12.0.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\..\packages\nanoFramework.CoreLibrary.1.12.0-preview.18\lib\mscorlib.dll</HintPath>
+      <HintPath>..\..\packages\nanoFramework.CoreLibrary.1.12.0-preview.19\lib\mscorlib.dll</HintPath>
       <Private>True</Private>
     </Reference>
   </ItemGroup>

source/UnitTestLauncher/packages.config

@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="nanoFramework.CoreLibrary" version="1.12.0-preview.18" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.CoreLibrary" version="1.12.0-preview.19" targetFramework="netnanoframework10" />
 </packages>