[Docs] Change Role to Api Name

[Rohith-Raju]

Closes: #7326

Documentation changes for user registration endpoint role property. In APIv4 and later, Roles don't have IDs and use names as their primary identifiers. The /users/register endpoint was updated accordingly, and the role property should actually be a Role's name, not its ID.

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• Documentation

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• This PR has documentation changes
• This PR DOES NOT FIX A SERIOUS SECURITY VULNERABILITY (see the Apache Software Foundation's security guidelines for details)

[ocket8888]

Updating the example is necessary, and good, but the actual description of the property under "Response Structure" for the PUT method. It currently reads:

"The integral, unique identifier of the highest permission Role which will be permitted to the user..."

but actually, it's not an integer anymore, it's a name

[Rohith-Raju]

@ocket8888 can I change it to

"A name, unique identifier of the highest permission Role which will be permitted to the user.."

[ocket8888]

I think instead you should change it to

"The name of the Role which will be given to the user..."

The bit about "permission level" refers to a legacy concept from the same era as the integral, unique IDs which has likewise been eliminated.