pgsql: Document that WAIT FOR may be interrupted by recovery conflicts

Document that WAIT FOR may be interrupted by recovery conflicts

Add a note to the WAIT FOR documentation explaining that sessions
using this command on a standby server may be interrupted by recovery
conflicts.  Some conflicts are unavoidable - for example, replaying
a tablespace drop terminates all backends unconditionally.

Discussion: https://postgr.es/m/CAPpHfds7oSCbZqob7ytT_Lso8fv-NW8LnedUTE4Krde%2B3rkJeA%40mail.gmail.com
Author: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/10484c2cc75be3746933d2052b18e8c28512f69e

Modified Files
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doc/src/sgml/ref/wait_for.sgml | 10 ++++++++++
1 file changed, 10 insertions(+)