ptest-runner: recipe update related to minor fix.

ptest-runner: recipe update related to minor fix.

A minor fix has been published regarding the need of a user
of being noticed when some run-ptest script fails.

Also Found modifications to ptest unit test stuff
* removed unnecessary code from unit test run_timeout_ptest
* added test case for run_ptest failure

Finally..
New content within contributions section of README.md.

[YOCTO #9752]

Signed-off-by: Edwin Plauchu <edwin.plauchu.camacho@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>