.travis.yml: allow failure for unreliable hosts

They will still run but they won't get in the way of the result.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200605154929.26910-6-alex.bennee@linaro.org>
1 file changed