fix: Type argument is not within its bounds.

Author: abubkr-hago

rxjava/src/main/java/com/parse/rxjava/Extensions.kt

@@ -7,7 +7,7 @@ import com.parse.boltsinternal.Task
 import io.reactivex.rxjava3.core.Completable
 import io.reactivex.rxjava3.core.Single
 
-fun <T> Task<T>.toSingle(): Single<T> {
+fun <T : Any> Task<T>.toSingle(): Single<T> {
     return Single.defer {
         this.waitForCompletion()
         if (isFaulted) {