[YSQL] Range columns of a primary key out-of-order

[robertpang]

When a user creates a YSQL table with a compound primary key, the range columns after the first implicit hash column are incorrectly created in the same order as they are in the columns' cardinal order, not in the order listed in the primary key. For example,

postgres=# create table t (r2 int, r1 int, h int, primary key (h, r1, r2));
CREATE TABLE
postgres=# \d t
                 Table "public.t"
 Column |  Type   | Collation | Nullable | Default
--------+---------+-----------+----------+---------
 r2     | integer |           | not null |
 r1     | integer |           | not null |
 h      | integer |           | not null |
Indexes:
    "t_pkey" PRIMARY KEY, btree (h, r1, r2)

The column order as appeared in yb-master is:

Column | ID | Type
------ | -- | ----------------------------
h      |  0 | int32 NOT NULL PARTITION KEY
r2     |  1 | int32 NOT NULL NOT A PARTITION KEY
r1     |  2 | int32 NOT NULL NOT A PARTITION KEY