Fixed user/pass issue for initialization scripts, added docs

[zachmu]

Fixes #2300

[github-actions]

	Main	PR
covering_index_scan_postgres	1122.85/s	1102.18/s	-1.9%
index_join_postgres	160.02/s	158.62/s	-0.9%
index_join_scan_postgres	207.79/s	205.03/s	-1.4%
index_scan_postgres	11.94/s	12.21/s	+2.2%
oltp_point_select	2399.37/s	2410.88/s	+0.4%
oltp_read_only	1865.73/s	1866.86/s	0.0%
select_random_points	126.36/s	131.13/s	+3.7%
select_random_ranges	820.90/s	835.91/s	+1.8%
table_scan_postgres	11.73/s	11.86/s	+1.1%
types_table_scan_postgres	5.36/s	5.47/s	+2.0%

[fulghum]

LGTM!

[github-actions]

	Main	PR
Total	42090	42090
Successful	17978	17977
Failures	24112	24113
Partial Successes1	5636	5636

	Main	PR
Successful	42.7132%	42.7109%
Failures	57.2868%	57.2891%

${\color{red}Regressions (1)}$

random

QUERY:          (SELECT unique1 AS random
  FROM onek ORDER BY random() LIMIT 1)
INTERSECT
(SELECT unique1 AS random
  FROM onek ORDER BY random() LIMIT 1)
INTERSECT
(SELECT unique1 AS random
  FROM onek ORDER BY random() LIMIT 1);
RECEIVED ERROR: expected row count 0 but received 1

Footnotes

1. These are tests that we're marking as Successful, however they do not match the expected output in some way. This is due to small differences, such as different wording on the error messages, or the column names being incorrect while the data itself is correct. ↩