tests: drivers: counter: nrf_rtc: Add delay in the test

Some Nordic platforms start counter with the delay and
test_short_relative_alarm test expects very early alarm,
just after starting the counter. Adding the delay which
is applicable only for counter based on Nordic RTC peripheral.

Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
1 file changed