Wait screen when test navigates to search text field

[b10n1k]

set a timeout before the send_key with the use of wait_screen_change

• Related ticket: https://progress.opensuse.org/issues/47138
• Needles: N/A
• Verification run: http://dhcp131.suse.cz/tests/99#step/yast2_i/11

[jknphy]

Would you mind to rephrase the title with something more descriptive, for instance:
Wait screen when <replace with short description of whatever alt-p does in this test>.
It is just for the purpose of looking at the history (for example using git log) and see better was done without entering into much detail.

[b10n1k]

@jknphy it s done