fix: docs side menu hiding under the navbar

[sdrejkarz]

Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes/features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce?

Side mine is no longer hiding on scrolling down on footer
Issue

[mkleszcz]

Unfortunately this fix doesn't work as expected, introducing another bug:
It cuts the menu at the bottom and does not allow to scroll and see all menu items

[sdrejkarz]

The only easy-to-go solution I can see here is

aside > div:first-child  {
    height: unset;
    overflow-y: auto;
    overflow-x: hidden;
}

but having two scrollbars (body + sidebar) is not something that we would like to have (or maybe I'm wrong).

Edit: this doesn't work properly either when the scroll is visible.