Change SwitchParameters from fields to properties (#13291)

src/Microsoft.PowerShell.Commands.Management/commands/management/TestConnectionCommand.cs

@@ -179,7 +179,7 @@ namespace Microsoft.PowerShell.Commands
         /// With this switch, standard ping and -Traceroute returns only true / false, and -MtuSize returns an integer.
         /// </summary>
         [Parameter]
-        public SwitchParameter Quiet;
+        public SwitchParameter Quiet { get; set; }
 
         /// <summary>
         /// Gets or sets the timeout value for an individual ping in seconds.

src/Microsoft.PowerShell.Commands.Utility/commands/utility/GetDateCommand.cs

@@ -44,7 +44,7 @@ namespace Microsoft.PowerShell.Commands
         /// Gets or sets whether to treat a numeric input as ticks, or unix time.
         /// </summary>
         [Parameter]
-        public SwitchParameter FromUnixTime;
+        public SwitchParameter FromUnixTime { get; set; }
 
         private DateTime _date;
         private bool _dateSpecified;