Market cleanup: Unnecessary write permission for LockedTable in AddBalance

[wadealexc]

Description

specs-actors/actors/builtin/market/market_actor.go

Lines 130 to 133 in a9f9f95

	msm, err := st.mutator(adt.AsStore(rt)).withEscrowTable(WritePermission).
	withLockedTable(WritePermission).build()
	builtin.RequireNoErr(rt, err, exitcode.ErrIllegalState, "failed to load state")

Market.AddBalance creates a marketStateMutation with WritePermission for st.LockedTable. As only st.EscrowTable is read from / written to, this permission is unnecessary and may cause extraneous state writes.

Recommendation

Remove the permission