chore(sea): bump KERNEL_REV to pick up DML num_modified_rows derivation

Points the pinned kernel at databricks-sql-kernel 81c6907 (PR #144),
which derives `num_modified_rows` for SEA DML from the result set so the
existing op-status wiring (readRichStatusFields → synthesizeThriftStatus)
surfaces numModifiedRows for INSERT/UPDATE/DELETE/MERGE at Thrift parity.

The napi contract (native/sea/index.d.ts / index.js) is unchanged — the
`numModifiedRows` accessor already existed; only its kernel-side
implementation changed — so no binding-contract update is needed.

Verified live against pecotesting (http_path2): SEA now returns
numModifiedRows 3/2/1/2 for INSERT/UPDATE/DELETE/MERGE, matching Thrift
exactly, and DML fetchAll() stays byte-identical across both backends
(the count row is read non-consuming).

Co-authored-by: Isaac

Author: msrathore-db

KERNEL_REV

@@ -1 +1 @@
-fcc459bbf3f39bf57e2ee02f14b99c0ec7a70123
+81c69078f8cbc59391824887a7d4be666ece9510