[nrf fromtree] tests: drivers: counter: basic_api: Tweak test timing

For slow processors it is possible that setting 1 ms alarm and
then canceling it could lead to alarm expiring before it is canceled
and that was not expected in the test. Increasing timeout to 1.5ms.

Signed-off-by: Krzysztof Chruściński <[email protected]>
(cherry picked from commit 331442f)

Author: nordic-krch

tests/drivers/counter/counter_basic_api/src/test_counter.c

@@ -887,7 +887,7 @@ static void test_cancelled_alarm_does_not_expire_instance(const struct device *d
 {
 	int err;
 	uint32_t cnt;
-	uint32_t us = 1000;
+	uint32_t us = 1500;
 	uint32_t ticks = counter_us_to_ticks(dev, us);
 	uint32_t top = counter_get_top_value(dev);