[Billing RP] Enable paging on enrollmentAccounts resource to improve SDK experience

[wilcobmsft]

This checklist is used to make sure that common issues in a pull request are addressed. This will expedite the process of getting your pull request merged and avoid extra work on your part to fix issues discovered during the review process.

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[lmazuel]

@hovsepm I got email context on this one, I'm saving you from this ;)

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