pgsql: Doc, more or less: uncomment tutorial example that was fixed lon

Doc, more or less: uncomment tutorial example that was fixed long ago.

Reverts a portion of commit 344190b7e.  Apparently, back in the
twentieth century we had some issues with multi-statement SQL
functions, but they've worked fine for a long time.

Daniel Westermann

Discussion: https://postgr.es/m/GVAP278MB04242DCBF5E31F528D53FA18D2A90@...

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dce62490818170b6479dfe08a28aae4bcdf7cc2d

Modified Files
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src/tutorial/funcs.source | 25 +++++++++++--------------
1 file changed, 11 insertions(+), 14 deletions(-)