Looking at the rendered output of README.adoc on Github, I realized
it still refers to Babeltrace 2.0.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: Ie67bb6a22e1f04560521296f4daac62d00ed5bc8
Reviewed-on: https://review.lttng.org/c/babeltrace/+/14117


Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>