This commit increases attempts on checks in this particular test from default 10 to 60.
This has been introduced to match worst case scenario where after 3 retries(5s) each dhcp waits 30 seconds before next 3 retries.
Commits yields to much more stable test behaviour.
Resolves: #1515
Signed-off-by: Ejub Sabic <ejub1946@outlook.com>