pgsql: Make spelling consistent

Make spelling consistent

"vertexes" -> "vertices"

Reported-by: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Discussion: /messages/by-id/CAJTYsWXFy1j_T82+M_S9kFxU414tQYnZQD-b82=oL_LbG_5fPQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d0eac3cafb0130b6da1eff03f2fd3afc448801c8

Modified Files
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src/backend/commands/propgraphcmds.c | 4 ++--
src/backend/rewrite/rewriteGraphTable.c | 12 ++++++------
src/test/regress/expected/graph_table.out | 6 +++---
src/test/regress/sql/graph_table.sql | 4 ++--
4 files changed, 13 insertions(+), 13 deletions(-)