[SPARK-18927][SS] MemorySink for StructuredStreaming can't recover from...

[SPARK-18927][SS] MemorySink for StructuredStreaming can't recover from checkpoint if location is provided in SessionConf

## What changes were proposed in this pull request?

Checkpoint Location can be defined for a StructuredStreaming on a per-query basis by the `DataStreamWriter` options, but it can also be provided through SparkSession configurations. It should be able to recover in both cases when the OutputMode is Complete for MemorySinks.

## How was this patch tested?

Unit tests

Author: Burak Yavuz <brkyvz@gmail.com>

Closes #16342 from brkyvz/chk-rec.