[SPARK-3715][Docs]minor typo

https://issues.apache.org/jira/browse/SPARK-3715

Author: WangTaoTheTonic <barneystinson@aliyun.com>

Closes #2567 from WangTaoTheTonic/minortypo and squashes the following commits:

9cc3f7a [WangTaoTheTonic] minor typo
Revert "[SPARK-1021] Defer the data-driven computation of partition bounds in so..."

This reverts commit 2d972fd84ac54a89e416442508a6d4eaeff452c1.

The commit was hanging correlationoptimizer14.
SPARK-2761 refactor #maybeSpill into Spillable

Moved `#maybeSpill` in ExternalSorter and EAOM into `Spillable`.

Author: Jim Lim <jim@quixey.com>

Closes #2416 from jimjh/SPARK-2761 and squashes the following commits:

cf8be9a [Jim Lim] SPARK-2761 fix documentation, reorder code
f94d522 [Jim Lim] SPARK-2761 refactor Spillable to simplify sig
e75a24e [Jim Lim] SPARK-2761 use protected over protected[this]
7270e0d [Jim Lim] SPARK-2761 refactor #maybeSpill into Spillable