pgsql: Fix incorrectly spelled city name

Fix incorrectly spelled city name

The correct spelling is Beijing, fix in regression test
and docs.

Author: JiaoShuntian <jiaoshuntian(at)gmail(dot)com>
Reviewed-by: Kirill Reshke <reshkekirill(at)gmail(dot)com>
Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Reviewed-by: Daniel Gustafsson <daniel(at)yesql(dot)se>
Discussion: https://postgr.es/m/ebfa3ec2-dc3c-4adb-be2a-4a882c2e85a7@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a9123db14a12e2e2dfb93dbbef4f2cdc2986023b

Modified Files
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doc/src/sgml/ref/alter_table.sgml | 2 +-
src/test/regress/expected/partition_merge.out | 16 +++++++-------
src/test/regress/expected/partition_split.out | 30 +++++++++++++--------------
src/test/regress/sql/partition_merge.sql | 6 +++---
src/test/regress/sql/partition_split.sql | 26 +++++++++++------------
5 files changed, 40 insertions(+), 40 deletions(-)