Deprecate "brand" in axe.configure

[WilcoFiers]

Up until about a year ago axe-core used axe.configure({ branding: { brand }}) to distinguish results produced by Attest products from results produced with axe. This is no longer necessary, since all Attest products have been renamed to axe DevTools. This should let us deprecate the brand property. As we're doing that, we might also want to consider changing the "branding" API. Maybe it could just be axe.configure({ application })?

[WilcoFiers]

Talked to @dylanb about this. What I think we should do is to deprecate branding.brand, and no longer use it to generate help URLs. It can only ever be axe, anything configured with branding.brand will be ignored as of axe-core 4.3. In addition, I think we should update axe.configure({ branding }) and allow branding to be a string, if it is, it is used as the application key in the help URL.

[padmavemulapati]

Validated with the latest develop branch axe-core code based,

// previously
axe.configure({
  branding: { application: 'axe' }
})
// current
able to configure `branding` with specified string.
axe.configure({ branding: 'axe' })

for ex: if I pass await axe.configure({ branding: 'axe' });
I am seeing helpURL:

If I pass await axe.configure({ branding: 'Padma' }); also
I am seeing helpURL with string "Padma"