Remove help button if there is no description content in panel

[rabmalin]

If there is no description parameter in add_panel call, in Customizer there is help button. Clicking on that does nothing. May be that button should be hidden if there is nothing to show about the panel.

Steps to reproduce:

• Add panel like

  $wp_customize->add_panel( 'sample_panel',
          array(
          'title'      => __( 'Sample Panel', 'text-domain' ),
          'priority'   => 100,
      )
  );
  

• Add section and settings under the panel.
• Go to Customize.
• When we are under the Sample Panel, help button is displayed it does not show anything.

[drebbits.web]

Update on the customize panel template

[westonruter]

In 36374:

Customizer: Hide help toggle button in panel when no description is supplied.

This aligns with the .customize-panel-description element which is also excluded if there is no description.

Props drebbits.web.
Fixes #35540.