* test/: PEP8 compliancy
- Make PEP8 compliant
* Python3 chokes on casting int to bytes (#24952)
But if we tell the formatter that the var is a number, it works
* updates all iosxr modules to support persistent socket
* adds iosxr action plugin to connect to device
* adds exec_command() to iosxr shared module
* fixes iosxr_config and iosxr_template local action
* update all unit test cases
* adds base test module for iosxr module testing
