add {{TEST_MINIO_ENDPOINT}} for local testing "with/without" docker + fix pgsql testing doc

[sommerf-lf]

while testing i found out that testing locally as documented in the changed README.md for pgsql isn't working because of the minio dependency. reworked this to by default be still docker, but allow for for local with only minio in docker and testing on bare metal.
also depending on this: fixed docs for running pgsql test

Closes: #32168 (by changing documentation for pgsql tests)
Closes: #32169 (by changing documentation, Makefile & pgsql.ini.tmpl: adding {{TEST_MINIO_ENDPOINT}})

sry for the combined pr, but when testing I ran into this issue and first thought they were related and now finally address the same problem: not beeing able to run pgsql integration tests as described in the according README.md

[sundaram2021]

have you raised an issue first when you found out something so that maintainers can have chat over it.

it will be helpful to raise an issue first (if not ) !

and how to reproduce it ?

Thaks

[sommerf-lf]

have you raised an issue first when you found out something so that maintainers can have chat over it.

it will be helpful to raise an issue first (if not ) !

and how to reproduce it ?

Thaks

Hi, sry I haven't raised an issue (yet).
Will revise and link. :)