Typos in the code and README

Applied patch to 'contrib/pg_overexplain/pg_overexplain.c' cleanly.
Applied patch to 'contrib/pg_plan_advice/pgpa_ast.c' cleanly.
Applied patch to 'contrib/pg_plan_advice/pgpa_ast.h' cleanly.
Applied patch to 'contrib/pg_plan_advice/pgpa_identifier.c' with conflicts.
Applied patch to 'contrib/pg_plan_advice/pgpa_join.c' cleanly.
Applied patch to 'contrib/pg_plan_advice/pgpa_planner.c' cleanly.
Applied patch to 'contrib/pg_stash_advice/stashfuncs.c' cleanly.
Applied patch to 'contrib/pg_stash_advice/stashpersist.c' cleanly.
Applied patch to 'contrib/pg_trgm/trgm_op.c' cleanly.
Applied patch to 'contrib/postgres_fdw/postgres_fdw.c' cleanly.
Applied patch to 'doc/src/sgml/pgstashadvice.sgml' cleanly.
Applied patch to 'doc/src/sgml/ref/alter_property_graph.sgml' cleanly.
error: doc/src/sgml/release-19.sgml: does not exist in index
Applied patch to 'src/backend/access/common/indextuple.c' cleanly.
Applied patch to 'src/backend/access/heap/heapam_visibility.c' cleanly.
Applied patch to 'src/backend/access/transam/multixact.c' cleanly.
Applied patch to 'src/backend/access/transam/xlog.c' cleanly.
Applied patch to 'src/backend/commands/explain_state.c' cleanly.
Applied patch to 'src/backend/commands/repack.c' cleanly.
Applied patch to 'src/backend/commands/vacuumparallel.c' cleanly.
Applied patch to 'src/backend/executor/execTuples.c' cleanly.
Applied patch to 'src/backend/executor/nodeModifyTable.c' with conflicts.
Applied patch to 'src/backend/libpq/be-secure-openssl.c' cleanly.
Applied patch to 'src/backend/parser/analyze.c' with conflicts.
Applied patch to 'src/backend/parser/parse_graphtable.c' cleanly.
Applied patch to 'src/backend/postmaster/autovacuum.c' with conflicts.
Applied patch to 'src/backend/postmaster/datachecksum_state.c' with conflicts.
Applied patch to 'src/backend/replication/logical/origin.c' cleanly.
Applied patch to 'src/backend/rewrite/rewriteGraphTable.c' with conflicts.
Applied patch to 'src/backend/statistics/extended_stats_funcs.c' with conflicts.
Applied patch to 'src/backend/storage/aio/method_worker.c' cleanly.
Applied patch to 'src/backend/storage/buffer/bufmgr.c' cleanly.
Applied patch to 'src/backend/storage/ipc/ipci.c' cleanly.
Applied patch to 'src/backend/storage/lmgr/lock.c' cleanly.
Applied patch to 'src/backend/storage/lmgr/predicate.c' cleanly.
Applied patch to 'src/backend/utils/adt/ruleutils.c' cleanly.
Applied patch to 'src/backend/utils/error/elog.c' cleanly.
Applied patch to 'src/bin/pg_combinebackup/t/011_ib_truncation.pl' cleanly.
Applied patch to 'src/bin/pg_dump/pg_dump.c' cleanly.
Applied patch to 'src/bin/pg_dump/pg_restore.c' with conflicts.
Applied patch to 'src/bin/pg_upgrade/check.c' cleanly.
Applied patch to 'src/common/wchar.c' cleanly.
Applied patch to 'src/include/access/tableam.h' with conflicts.
Applied patch to 'src/include/postmaster/datachecksum_state.h' with conflicts.
Applied patch to 'src/test/modules/test_checksums/t/003_standby_restarts.pl' cleanly.
Applied patch to 'src/test/modules/test_checksums/t/005_injection.pl' cleanly.
Applied patch to 'src/test/modules/test_checksums/test_checksums.c' cleanly.