Allow the cluster shutdown in some cases when dtx recovery hang happens. (#8873)
Allow the cluster shutdown in some cases when dtx recovery hang happens. (#8873)

We've seen this when fts detects 'double fault'. In such case,
dtx recovery can not proceed and newly created postgres backend could
hang, waiting for dtx recovery finishing. Changing the code to make
the cluster be able to stop in fast mode; Also those backends
should quit if postmaster is dead.

Co-Authored-by: Paul Guo <e78f8a884cebd97fb3b249dc32d233761d2e480a@pivotal.io>
Reviewed-by: Ning Wu <57195575ccb690f85902294025b39c9888c369e6@pivotal.io>
Reviewed-by: Ashwin Agrawal <924bf3437ad315c1c74f9c41d83153600b05f548@pivotal.io>
Reviewed-by: Ashwin Agrawal <924bf3437ad315c1c74f9c41d83153600b05f548@pivotal.io>
Reviewed-by: Asim R P <24f343109504afa210657d296a0873118cbd2b97@pivotal.io>
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