Upgrade release version to 5.3.1 (#24)

Author: sunnywu

UID2.Client.nuspec

@@ -2,7 +2,7 @@
 <package>
   <metadata>
     <id>UID2.Client</id>
-    <version>5.3.0</version>
+    <version>5.3.1</version>
     <title>UID2 Client C# SDK</title>
     <authors>UID2 team</authors>
     <owners>UID2 team</owners>

src/UID2.Client/UID2Client.cs

@@ -134,7 +134,7 @@ public async Task<RefreshResponse> RefreshAsync(CancellationToken token)
 
         private string GetAssemblyNameAndVersion()
         {
-            var version = "5.3.0";
+            var version = "5.3.1";
             return "uid-client-net-" + version;
         }