pgsql: Simplify translatable messages for tuple value details in confli

Simplify translatable messages for tuple value details in conflict.c.

append_tuple_value_detail() constructed user-visible messages using
separately translated fragments such as ": ", ", ", and ".",. This
makes correct translation difficult or impossible in some languages.

Refactor append_tuple_value_detail() to move all punctuation and
sentence construction to the callers, which now use a single
translatable string with a %s placeholder for the tuple data.

Reported-by: David Rowley <dgrowleyml(at)gmail(dot)com>
Author: vignesh C <vignesh21(at)gmail(dot)com>
Reviewed-by: Hayato Kuroda <kuroda(dot)hayato(at)fujitsu(dot)com>
Reviewed-by: Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
Reviewed-by: Zhijie Hou <houzj(dot)fnst(at)fujitsu(dot)com>
Reviewed-by: Peter Smith <smithpb2250(at)gmail(dot)com>
Discussion: https://postgr.es/m/227279.1775956328%40sss.pgh.pa.us#8f3a5f50543556c60cc5a13270cb7ba4
Discussion: https://postgr.es/m/CAApHDvohYOdrvhVxXzCJNX_GYMSWBfjTTtB6hgDauEtZ8Nar2A@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bf3ead60751488f5c65434fa7ea770a9f6031db0

Modified Files
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src/backend/replication/logical/conflict.c | 223 +++++++++++++++++++----------
1 file changed, 148 insertions(+), 75 deletions(-)