docs: Correct profile examples in docs Playground widget

[dkoch74]

Correct profile examples in docs Playground widget

1. Revised payment handler example to include "config" property within payment handler only for business profile - not platform profile. The config section is irrelevant for both of the example handlers in the platform profile context.
2. Revised "Discovery" step to reflect that the shown response is the business profile in its entirety. The filtering/intersection occurs in the "Negotiation" step that follows.

Resolves issues identified in issue #277

Type of change

• Documentation update

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Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation

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[archrao]

LGTM. The separation of platform and business handlers clarifies the discovery step well.