This package was originally internal, but was moved out when BuildKit
used it for its integration tests. That's no longer the case, so we
can make it internal again.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Integration tests will now configure clients to propagate traces as well
as create spans for all tests.
Some extra changes were needed (or desired for trace propagation) in the
test helpers to pass through tracing spans via context.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
