pull: don't say that merge is "the default strategy"

Git no longer has a default strategy for reconciling divergent branches,
because there's no way for Git to know which strategy is appropriate in
any particular situation.

The initially proposed version in [*], that eventually became
031e2f7 (pull: abort by default when fast-forwarding is not
possible, 2021-07-22), dropped this phrase from the message, but
it was left in the final version by accident.

* https://lore.kernel.org/git/[email protected]/

Signed-off-by: Alex Henrie <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: alexhenrie

builtin/pull.c

@@ -939,7 +939,7 @@ static void show_advice_pull_non_ff(void)
 		 "You can do so by running one of the following commands sometime before\n"
 		 "your next pull:\n"
 		 "\n"
-		 "  git config pull.rebase false  # merge (the default strategy)\n"
+		 "  git config pull.rebase false  # merge\n"
 		 "  git config pull.rebase true   # rebase\n"
 		 "  git config pull.ff only       # fast-forward only\n"
 		 "\n"