Fix typo in Server-to-Server auth scope parameter name

[JPelka]

Description

This page specifies list of parameters required by IMS Server-to-Server authentication OAuth flow. The name of parameter is scopes while scope is actually expected. Only the sample code contained correct spelling.

Related Issue

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Motivation and Context

It may prevent people from encountering a frustrating error indicating mismatch of scopes required/available, while the real cause is a mis-spelled parameter.

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• [ x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] I have signed the Adobe Open Source CLA.
• [x] My code follows the code style of this project.
• [x] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [ ] All new and existing tests passed.