[PATCH 2 of 4 accept-scripts] land: document regression I introduced in 214aea0ce915

[Augie Fackler]

# HG changeset patch
# User Augie Fackler <raf at durin42.com>
# Date 1541633597 18000
#      Wed Nov 07 18:33:17 2018 -0500
# Node ID 93766fc0dafe96a41a18ddd74e1408fabd7d63ad
# Parent  fa593e6a69f59fef0a10a03671ec14b1aa59a283
land: document regression I introduced in 214aea0ce915

In the process of fixing merges, it turns out I dropped the code that
wrote acceptance information into the .hg/take.log in the destination
repo. Tragically, there was no test coverage for this, and as a result
we have no information on landing of changes since April. :(

diff --git a/tests/test-land.t b/tests/test-land.t
--- a/tests/test-land.t
+++ b/tests/test-land.t
@@ -102,4 +102,6 @@ We expect to land 3::6.
   |
   o  0:1ea7 default
   
+The `land` script should have written useful information in .hg/take.log in
+the destination repository. BUG: this doesn't work :(
   $ cat .hg/take.log