Fix missing coma in $accumulator example and duplicate "to"

[GromNaN]

DESCRIPTION

Fix small typos.

STAGING

JIRA

BUILD LOG

Self-Review Checklist

• [ ] Is this free of any warnings or errors in the RST?
• [ ] Is this free of spelling errors?
• [ ] Is this free of grammatical errors?
• [ ] Is this free of staging / rendering issues?
• [ ] Are all the links working?

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