### What changes were proposed in this pull request?
This pr aims to add a new `table` API in DataStreamReader, which is similar to the table API in DataFrameReader.
### Why are the changes needed?
Users can directly use this API to get a Streaming DataFrame on a table. Below is a simple example:
Application 1 for initializing and starting the streaming job:
```
val path = "/home/yuanjian.li/runtime/to_be_deleted"
val tblName = "my_table"
// Write some data to `my_table`
spark.range(3).write.format("parquet").option("path", path).saveAsTable(tblName)
// Read the table as a streaming source, write result to destination directory
val table = spark.readStream.table(tblName)
table.writeStream.format("parquet").option("checkpointLocation", "/home/yuanjian.li/runtime/to_be_deleted_ck").start("/home/yuanjian.li/runtime/to_be_deleted_2")
```
Application 2 for appending new data:
```
// Append new data into the path
spark.range(5).write.format("parquet").option("path", "/home/yuanjian.li/runtime/to_be_deleted").mode("append").save()
```
Check result:
```
// The desitination directory should contains all written data
spark.read.parquet("/home/yuanjian.li/runtime/to_be_deleted_2").show()
```
### Does this PR introduce _any_ user-facing change?
Yes, a new API added.
### How was this patch tested?
New UT added and integrated testing.
Closes#29756 from xuanyuanking/SPARK-32885.
Authored-by: Yuanjian Li <yuanjian.li@databricks.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
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