docs: keep docs/ship-policy.md at the reviewed text; its GST-980 sentence already states the carry rule

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

docs/ship-policy.md

@@ -1359,7 +1359,6 @@ receipt when the base moves:
 | a rebase or force-push onto a tree the receipt covers, product diff against the new base unchanged | carries (`carry.ancestry: rewritten`) |
 | any other rebase or force-push | a fresh /ship (`RECEIPT_CARRY_TREE_MISMATCH`) |
 | a stacked PR whose parent landed (squash or merge), retargeted to the base with the base merged in, HEAD's product diff exactly the one reviewed against the parent branch | carries (reason `stack parent <branch> landed`) |
-| a stamp on the branch's own rows in a stamp file the branch also changed as product: every changed line at a branch-added position, the file's mode unchanged, the base not touching it, the rest of the product diff unchanged | carries (reason `a stamp on the branch's own rows (<file>)`) |
 
 **Stacked PRs (#3570).** A child PR's receipt is written against its parent
 branch, so its `base` names that branch and its `product_patch_id` is the