Navbar without hamburger unnecessary css

[Stelu77]

Describe the bug
When using the mj-navbar without hamburger menu there are still a large CSS block rendered in the head for the menu feature.

To Reproduce
Try it out sample

Expected behavior
This css block should only be rendered in HTML if hamburger attribute are set.

<style type="text/css">
    noinput.mj-menu-checkbox {
      display: block !important;
      max-height: none !important;
      visibility: visible !important;
    }

    @media only screen and (max-width:480px) {
      .mj-menu-checkbox[type="checkbox"]~.mj-inline-links {
        display: none !important;
      }

      .mj-menu-checkbox[type="checkbox"]:checked~.mj-inline-links,
      .mj-menu-checkbox[type="checkbox"]~.mj-menu-trigger {
        display: block !important;
        max-width: none !important;
        max-height: none !important;
        font-size: inherit !important;
      }

      .mj-menu-checkbox[type="checkbox"]~.mj-inline-links>a {
        display: block !important;
      }

      .mj-menu-checkbox[type="checkbox"]:checked~.mj-menu-trigger .mj-menu-icon-close {
        display: block !important;
      }

      .mj-menu-checkbox[type="checkbox"]:checked~.mj-menu-trigger .mj-menu-icon-open {
        display: none !important;
      }
    }
  </style>

MJML environment (please complete the following information):
Try it out editor.

[iRyusa]

😬 that's really interesting to fix but with current implem I don't think we can fix it yet...

Keeping this open if anyone willing to work on this.

Nice finding!