[10.x.x] GSG-546 - Updates to README (Backport of commit from #5610)

[sarah-welton]

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Checklist for PR maker

• Have you added a backport label (if needed)? For example, the need-backport-* label. After you backport the PR, the label changes to backported-*.
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Purpose of this PR

Why is this PR needed, what hard problem is it solving/fixing?

Made changes to README file to satisfy changes needed by GSG-546

Backports are needed for 7.x.x

Related to #5599, #5609, and #5610

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Testing status

Describe what manual/automated tests were performed for this PR

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Comments to reviewers

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