ci: Fix the corstone1000-mps3 lava job prompts

Lava uses pexpect to search for prompts, which includes all the output
on the connection. Having a prompt with a wildcard like (*.) in
beginning of the search string, the pexpect is asked to match against
an extremely large and growing input string, which causes significant
delays in processing job output.

This fixes the sanity and ptest job which takes more than 6 hours on
lava farm to reach the boot stage. Also update the timeouts of tasks
in the job.

Signed-off-by: Vikas Katariya <vikas.katariya@arm.com>