Chore (toolbox): improved shortcuts visibility when tool exports array of toolbox items

[e11sy]

Problem

For now if tool exports array of toolbox items via

public static get toolbox(): ToolboxConfig {
    return [ 'array of toolbox items here' ]

we would see same shortcut for each of the toolbox items:

Solution

Now we would write shortcut only for first toolbox item of each tool

Changes

• now toPopoverItem method of the toolbox forms secondaryLavel only for first toolbox item of each tool
• added test for toolbox.cy.ts that checks new functionality
• changed description of the tool-settings data property