pgsql: Revert "pg_collation_actual_version() -> pg_collation_current_ve

Revert "pg_collation_actual_version() -> pg_collation_current_version()."

This reverts commit 9cf184cc0599b6e65e7e5ecd9d91cd42e278bcd8.  Name
change less well received than anticipated.

Discussion: https://postgr.es/m/afcfb97e-88a1-a540-db95-6c573b93bc2b%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8556267b2b1b8e1c26037c4c25cf390ee5afb5d9

Modified Files
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doc/src/sgml/func.sgml                         |  8 ++++----
src/backend/commands/collationcmds.c           |  2 +-
src/backend/utils/adt/pg_locale.c              | 14 +++++++-------
src/include/catalog/catversion.h               |  2 +-
src/include/catalog/pg_proc.dat                |  4 ++--
src/test/regress/expected/collate.icu.utf8.out |  6 +++---
src/test/regress/sql/collate.icu.utf8.sql      |  6 +++---
7 files changed, 21 insertions(+), 21 deletions(-)