- Ignore JS fixtures
- Ignore qa directory
- Rewrite concern specs to put concern name first

This shared example was only used by this spec so having it in a
separate file provided no benefit, at the cost of clarity. This also
reduces the three `it` blocks into a single test with
`aggregate_failures`.

This would fix long standing failures running tests on
my development machine, which set `Gitlab.config.gitlab.host`
to another host because it's not my local computer. Now I
finally cannot withstand it and decided to fix them once and
for all.