Fix dependency declaration in nuspec (#1)

Author: networkfusion

nanoFramework.System.IO.Ports.nuspec

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <package xmlns="http://schemas.microsoft.com/packaging/2012/06/nuspec.xsd">
   <metadata>
     <id>nanoFramework.System.IO.Ports</id>
@@ -21,8 +21,8 @@ This package requires a target with System.IO.Ports v$nativeVersion$.</descripti
     <tags>nanoFramework C# csharp netmf netnf System.IO.Ports</tags>
     <dependencies>
       <dependency id="nanoFramework.CoreLibrary" version="1.10.3-preview.11" />
-      <dependency id="nanoFramework.Hardware.Esp32" version="1.3.3-preview.14" />
       <dependency id="nanoFramework.Runtime.Events" version="1.9.0-preview.26" />
+      <dependency id="nanoFramework.System.Collections" version="1.2.0-preview.51" />
       <dependency id="nanoFramework.System.Text" version="1.1.1-preview.49" />
     </dependencies>
   </metadata>
@@ -37,4 +37,4 @@ This package requires a target with System.IO.Ports v$nativeVersion$.</descripti
     <file src="assets\nf-logo.png" target="images" />
     <file src="LICENSE.md" target="" />
   </files>
-</package>
+</package>