Merging of JS and GO test branches

[akvlad]

Goal

Have JS e2e test branch refactored the same way as the GO branch.

Why

Currently we have main js branch with a messy one-function e2e test
On the other hand there's a cloki-go branch refactored into multiple test cases running in a special order.
We need the main branch to be refactored the same way.

How

There are two ways of doing this

I We can repeat the same refactoring for the main branch

Split one test case into a set of smaller cases and make a mechanism to run them in a strict order

II We can merge cloki-go and main branches

Compare two branches. Compare the test cases for each branch.

The second way is harder but preferred because we get understanding the API difference between versions.