Bumping .NET assembly version number before 5.16.5 release as there were changes

Source commit: 018ea272f7eb2cfd1027205d32a23aedf32e7b3c

dotnet/properties/AssemblyInfo.cs

@@ -35,7 +35,7 @@ namespace WinSCP
     {
         public const string UndefinedProductVersion = "9.9.9.9";
 
-        public const string Version = "1.7.1.0";
+        public const string Version = "1.7.2.0";
         public const string ProductVersion = "5.16.5.0";
     }
 }