Обсуждение: pgsql: Replace link to Hunspell with the current homepage

Replace link to Hunspell with the current homepage

The Hunspell project moved from Sourceforge to Github sometime
in 2016, so update our links to match the new URL.  Backpatch
the doc changes to all supported versions.

Discussion: https://postgr.es/m/DC9A662A-360D-4125-A453-5A6CB9C6C4B4@yesql.se
Backpatch-through: v11

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f1d042b21dfdac069601fe97b7b7ba572dd0abe2

Modified Files
--------------
doc/src/sgml/textsearch.sgml      | 2 +-
src/include/tsearch/dicts/spell.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)