pgsql: Doc: manually break lines in wide UUID examples.

Doc: manually break lines in wide UUID examples.

Buildfarm member crake has been complaining "WARNING: The contents of
fo:inline line 1 exceed the available area in the inline-progression
direction by 20500 millipoints. (See position 23808:106)" since
ba57dcfdc went in. The other doc-building animals are not showing
this warning, and I don't see it on my RHEL8 workstation either, but
I was able to reproduce it on a Fedora 41 box. So apparently this
is due to a recent-ish change in DocBook's line-breaking heuristics,
which caused it to cope less well with the UUIDs in these examples.
Put in some zero-width spaces to encourage the PDF toolchain to
break these lines in a better place. (Only one of these examples
actually needs this today, but I marked up all three to ensure that
they get wrapped in a consistent way.)

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a6524105d20b190fb4f5b2116e044e29be88f215

Modified Files
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doc/src/sgml/func.sgml | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)