pgsql: Change overly strict Assert in TransactionGroupUpdateXidStatus.

Change overly strict Assert in TransactionGroupUpdateXidStatus.

This Assert thought that an overflowed transaction can never get registered
for the group update.  But that is not true, because even when the number
of children for a transaction got reduced, the overflow flag is not
changed. And, for group update, we only care about the current number of
children for a transaction that is being committed.

Based on comments by Andres Freund, remove a redundant Assert in
TransactionIdSetPageStatus as we already had a static Assert for the same
condition a few lines earlier.

Reported-by: Vignesh C
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Backpatch-through: 11
Discussion: https://postgr.es/m/CAFiTN-s5=uJw-Z6JC9gcqtBSjXsrHnU63PXBrA=pnBjqnkm5UA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/af3290f5e790dcd1be3ac209be1805626f4ebac8

Modified Files
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src/backend/access/transam/clog.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)