[SPARK-15382][SQL] Fix a bug in sampling with replacement

## What changes were proposed in this pull request?
This pr to fix a bug below in sampling with replacement
```
val df = Seq((1, 0), (2, 0), (3, 0)).toDF("a", "b")
df.sample(true, 2.0).withColumn("c", monotonically_increasing_id).select($"c").show
+---+
|  c|
+---+
|  0|
|  1|
|  1|
|  1|
|  2|
+---+
```

## How was this patch tested?
Added a test in `DataFrameSuite`.

Author: Takeshi YAMAMURO <linguin.m.s@gmail.com>

Closes #14800 from maropu/FixSampleBug.