common_text_fixtures removed before time

[emanuel-schmid]

In pr #1273 the module climada.test.common_text_fixtures has been removed while it was still required by climada.test.test_trajectories

I've temporarily recovered that module for the sake of running (let alone passing) the integration tests (2b19cf8).

The failing tests need to be adapted to the replacement climada.test.conftest I suppose, then the module can be removed for good.

[spjuhel]

Ahhhh I see, I did update but only in split 5 (I thought it would be merged by then....)
Let me fix this!

[spjuhel]

These integration tests should not have been merged in #1200, that was the issue.
I've updated them in #1283 !