Add comment explaining remote debug setting

Author: rjmholt

src/PowerShellEditorServices/Services/PowerShell/Debugging/PowerShellDebugContext.cs

@@ -67,6 +67,8 @@ public Task<DscBreakpointCapability> GetDscBreakpointCapabilityAsync(Cancellatio
 
  public void EnableDebugMode()
  {
+ // This is required by the PowerShell API so that remote debugging works.
+ // Without it, a runspace may not have these options set and attempting to set breakpoints remotely can fail.
  _psesHost.Runspace.Debugger.SetDebugMode(DebugModes.LocalScript | DebugModes.RemoteScript);
  }