### What changes were proposed in this pull request?
Only throw logWarning when `PUSH_BASED_SHUFFLE_ENABLED` is set to true and `canDoPushBasedShuffle` is false
### Why are the changes needed?
Currently, this logWarning will still be printed out even when `PUSH_BASED_SHUFFLE_ENABLED` is set to false, which is unnecessary.
### Does this PR introduce _any_ user-facing change?
No.
### How was this patch tested?
Passed existing UT.
Closes#33984 from rmcyang/SPARK-36705-follow-up.
Authored-by: Minchu Yang <minyang@minyang-mn3.linkedin.biz>
Signed-off-by: Mridul Muralidharan <mridul<at>gmail.com>
(cherry picked from commit 2d7dc7c7ce)
Signed-off-by: Mridul Muralidharan <mridulatgmail.com>
4a486f40cf