Fix how some lists are displayed by psql \d+

Hi.

I recently saw that the psql \d+ lists for "Partitions:" are not
aligned in quite the same way as other lists ("Publications:" etc)
because they use indents and line breaks differently. e.g. See below:

test_pub=# \d+ part1
Partitioned table "public.part1"
Column | Type | Collation | Nullable | Default | Storage |
Compression | Stats target | Description
--------+---------+-----------+----------+---------+---------+-------------+--------------+-------------
a | integer | | | | plain |
| |
Partition of: t1 FOR VALUES FROM (0) TO (50)
Partition constraint: ((a IS NOT NULL) AND (a >= 0) AND (a < 50))
Partition key: RANGE (a)
Publications:
"pub1"
"pub2"
"pub_only"
Partitions: part1_1 FOR VALUES FROM (0) TO (25), PARTITIONED,
part1_2 FOR VALUES FROM (25) TO (50)

~~~

PSA v1
0001 - Fix (common code) lists for "Partitions:" and "Child tables:"
0002 - Fix list for "Inherits:" in the same way

~~~

The *patched* result for the same example now looks like below. Notice
that in passing I also removed the comma separators, which are not
present in the other footer lists.

test_pub=# \d+ part1
Partitioned table "public.part1"
Column | Type | Collation | Nullable | Default | Storage |
Compression | Stats target | Description
--------+---------+-----------+----------+---------+---------+-------------+--------------+-------------
a | integer | | | | plain |
| |
Partition of: t1 FOR VALUES FROM (0) TO (50)
Partition constraint: ((a IS NOT NULL) AND (a >= 0) AND (a < 50))
Partition key: RANGE (a)
Publications:
"pub1"
"pub2"
"pub_only"
Partitions:
part1_1 FOR VALUES FROM (0) TO (25), PARTITIONED
part1_2 FOR VALUES FROM (25) TO (50)

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Kind Regards,
Peter Smith.
Fujitsu Australia