docs(plans): record the S20-A step 10 and step 11 MRs in the status table

Fill two Status table cells in the S20-A plan.

Step	Merge request
10, npm remote reap	!1746 (merged)
11, Maven remote reap	!1738 (merged)

Row 9 was part of this change before the rebase onto main at 924de71b. main now carries that cell, so this merge request no longer touches row 9.

The plan Status table has a single writer, so step merge requests do not edit the plan file. Each reference lands here instead, at the time the step merge request opens.

Rows 10 and 11 sit on consecutive lines of one table. Two step branches carried their own hunk for these rows before this change, which is the collision the single-writer rule prevents.

This merge request records references only. It changes no step, no scope, and no acceptance text.

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