Update InstallReferrers.kt

Author: gdeluna-branch

Branch-SDK/src/main/java/io/branch/coroutines/InstallReferrers.kt

@@ -11,7 +11,6 @@ import io.branch.referral.Defines.Jsonkey
 import io.branch.referral.PrefHelper
 import io.branch.referral.util.classExists
 import io.branch.referral.util.huaweiInstallReferrerClass
-import io.branch.referral.util.isHyperOS
 import io.branch.referral.util.samsungInstallReferrerClass
 import io.branch.referral.util.xiaomiInstallReferrerClass
 import kotlinx.coroutines.CompletableDeferred