In conn_close_if_marked(), we can decide to keep a connection open that still
has data to flush on the wire if it is being rate limited on the write side.
However, in this process, we were also looking at the read() side which can
still have token in its bucket and thus not stop the reading. This lead to a
BUG() introduced in 0.3.4.1-alpha that was expecting the read side to be
closed due to the rate limit but which only applies on the write side.
This commit removes any bandwidth check on the read side and simply stop the
read side on the connection regardless of the bucket state. If we keep the
connection open to flush it out before close, we should not read anything.
Fixes#27750
Signed-off-by: David Goulet <dgoulet@torproject.org>