reorder_chunk does not do correct attribute mapping between chunk and hypertable

[svenklemm]

Reorder fails to convert column references in the used index from the hypertable to the chunk attributes leading to wrong results or spurious errors when the index references columns with different attnum between chunk and hypertable.

To reproduce:

dev=# create table o(c1 timestamptz,c2 text, c3 text);
CREATE TABLE
Time: 17.549 ms
dev=# select create_hypertable('o','c1');
NOTICE:  00000: adding not-null constraint to column "c1"
DETAIL:  Time dimensions cannot have NULL values.
LOCATION:  dimension_add_not_null_on_column, dimension.c:1055
 create_hypertable
-------------------
 (7,public,o,t)
(1 row)
Time: 31.077 ms
dev=# alter table o drop column c2;
ALTER TABLE
Time: 19.402 ms
dev=# alter table o add column c4 text;
ALTER TABLE
Time: 7.055 ms
dev=# create unique index on o(c1,c4);
CREATE INDEX
Time: 18.790 ms
dev=# insert into o select '2000-01-01','foo','foo';
INSERT 0 1
Time: 53.000 ms
dev=# insert into o select '2000-01-01','foo','bar';
INSERT 0 1
Time: 8.321 ms

dev=# select reorder_chunk('_timescaledb_internal._hyper_7_2580_chunk','o_c1_c4_idx');
ERROR:  23505: could not create unique index "pg_temp_5257022__hyper_7_2580_chunk_o_c1_c4_idx"
DETAIL:  Key (c1, c3)=(2000-01-01 00:00:00+01, foo) is duplicated.
SCHEMA NAME:  _timescaledb_internal
TABLE NAME:  pg_temp_5257022
CONSTRAINT NAME:  pg_temp_5257022__hyper_7_2580_chunk_o_c1_c4_idx
LOCATION:  comparetup_index_btree, tuplesort.c:4219
Time: 38.982 ms