Revert "detect the right transport for the client in tests"

This reverts commit d33b01d6355b6e7c7339c07d7d8f36ffedabb018.
Lay down computed configuration and use that source for all of the tests
Don't remove the root_dir, the tests suite takes care of that
Call `verify_env` on `transplant_configs`
Remove stray print and commented out entries
Store evaluated configs as `cls` attributes
Remove unused imports
Use `SaltClientTestCaseMixIn` instead
Tempdir under `integration.SYS_TMP_DIR` and use `AdaptedConfigurationTestCaseMixIn`
Leave any cleanup for the end
Call the right parent class
Remove unused imports
Disable PEP8 E256
No need for late imports. Use `AdaptedConfigurationTestCaseMixIn`.
Copy the extension modules into the new master `root_dir`
Skip tests on missing `empty_dir`
Skip test for now.

/CC: @cachedout
Fix imports
Add missing `path` key to the load.

Minor PEP-8, global variable `load` -> `LOAD`
Log on missing required keys in the load