Multiple updates to api tests

1. Removed references to decorators.($func) by importing them directly
2. Imported ddt.data as ddt_data to differentiate it from decorators.data - This change is done inorder to make the api tests **consistent** with ui/cli tests
3. Added pylint disables to make pylint happy for all the files in this commit
Line 7 and 8 could be joined:

```python
In [1]: from ddt import data as ddt_data, ddt

In [2]: ddt
Out[2]: <function ddt.ddt>

In [3]: ddt_data
Out[3]: <function ddt.data>
```