Revert "fix cloud.lxc usage of kwargs which seem to have changed"

This reverts commit a7f1508645f8a9f611f7631c19677a7c7895431c.
Properly handle non-string args

This fixes arguments which came from a non-string (i.e. API) source.
This issue was introduced recently in pull request #11368.
Merge pull request #11462 from terminalmage/non-string-args

Properly handle non-string args