Change the prompt wait after crash approach

[mpagot]

HanaSR test has a command to crash the SUT to be sent through ssh to the remote SUT. There is code after sending this command to check the prompt is available and eventually unlock it.
Fix an issue where this prompt checking break the next command sending procedure.

• Related ticket: https://jira.suse.com/browse/TEAM-9658 https://jira.suse.com/browse/TEAM-9652

Verification run:

sle-15-SP6-HanaSr-Aws-Byos-x86_64-Build15-SP6_2024-09-19T02:04:03Z-hanasr_aws_test_fencing_sbd ec2_r4.8xlarge

• http://openqaworker15.qa.suse.cz/tests/297858

sle-15-SP6-HanaSr-Azure-Byos-x86_64-Build15-SP6_2024-09-19T02:04:03Z-hanasr_azure_test_saptune_msi az_Standard_E4s_v3

• http://openqaworker15.qa.suse.cz/tests/297859 :green:

Crash command typed here at 17:31:28

[2024-09-20T17:31:28.601214+02:00] [debug] [pid:58842] <<< consoles::serial_screen::type_string(cmd="backend_type_string", text="ssh

Execution immediately returns from script_run and run_ssh_command. At this point stop_hana calls wait_serial at 17:31:28

[2024-09-20T17:31:28.605581+02:00] [debug] [pid:58700] tests/sles4sap/publiccloud/hana_sr_takeover.pm:62 called sles4sap_publiccloud::stop_hana -> lib/sles4sap_publiccloud.pm:408 called testapi::wait_serial

Prompt is detected in no time 17:31:28, was not blocked.

[2024-09-20T17:31:28.839548+02:00] [info] [pid:58842] ::: consoles::serial_screen::read_until: Matched output from SUT in 3 loops & 0.231783708790317 seconds: # 

The new code from the PR sends a ret to get one more prompt for the next serial_run to check

[2024-09-20T17:31:28.842139+02:00] [debug] [pid:58700] <<< testapi::send_key(key="ret", wait_screen_change=0)

Here the next test stage that sends the next command

[2024-09-20T17:31:28.846574+02:00] [debug] [pid:58700] <<< testapi::script_run(cmd="nc -vz -w 1

And now, with the PR fix, it get is immediately

[2024-09-20T17:31:28.849796+02:00] [info] [pid:58842] ::: consoles::serial_screen::read_until: Matched output from SUT in 2 loops & 0.000877343816682696 seconds: # 
[2024-09-20T17:31:28.850659+02:00] [debug] [pid:58700] >>> testapi::wait_serial: # : ok

[github-actions]

Great PR! Please pay attention to the following items before merging:

Files matching lib/**.pm:

• Consider adding or extending unit tests in t/

This is an automatically generated QA checklist based on modified files.

[alvarocarvajald]

LGTM

[lpalovsky]

LGTM