test: add acala & karura to e2e tests and some improvements (#1273)

* some improvements

* no need to hardcode chains

* add acala for e2e tests

* add karura

* able to configure url

* fix

* fix

* Update e2e-tests/latest/endpoints/acala.ts

Co-authored-by: Tarik Gul <[email protected]>

---------

Co-authored-by: Tarik Gul <[email protected]>