Avoid using 5 shards when number of tests are low
Avoid using 5 shards when number of tests are low

Fixes a false positive in test result when number of tests are lower than number of shards and browserstack simply errors out

dimagi/commcare-android,dimagi/commcare-android,dimagi/commcare-android,dimagi/commcare-android,dimagi/commcare-android,dimagi/commcare-android