pgsql: Remove PlannedStmt->resultRelations in favor of resultRelationRe

Remove PlannedStmt->resultRelations in favor of resultRelationRelids

PlannedStmt->resultRelations was an integer list of range table indexes
because at the time it was added (to Query), the Bitmapset data type did
not yet exist in Postgres.

0f4c170cf3b added a Bitmapset of result relations, so remove the integer
list of RTIs and use the more compact resultRelationRelids.

Discussion: https://postgr.es/m/CAApHDvqAOeOwCKh9g0gfxWa040%3DHyc7_oA%3DC59rjod8kXJDWyw%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/39dcd10a2c493821cc88a9f8d17677507571e87d

Modified Files
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contrib/pg_overexplain/pg_overexplain.c | 5 +++--
src/backend/executor/execParallel.c     | 1 -
src/backend/executor/execUtils.c        | 2 +-
src/backend/optimizer/plan/planner.c    | 1 -
src/include/nodes/plannodes.h           | 4 ----
5 files changed, 4 insertions(+), 9 deletions(-)