query_supervisor configuration and parallel queries support and functionl test refactoring

Marcin authored 2 years ago and Marcin committed 2 years ago

A databses for tests are created with double quoted name and were dropped
without quoting its names. Unqoted identifires are made lowered case
and quoted preserve letters cases, so when a test database
containded capital letters, then DROP command did not find a database
to drop.

Marcin authored 2 years ago and Marcin committed 2 years ago

now each test can run give/when/then/error functions for each role
the functions are optional, instead of add functions with empty body,
now it is possible to omit them
update documentation

Marcin authored 2 years ago and Marcin committed 2 years ago

fix parallel queries crash when loading supervisor
background workers do not check limits, only backend do this
add functional tests