Signed-off-by: maipbui <maibui@microsoft.com>
Dependency: [PR (#12065)](https://github.com/sonic-net/sonic-buildimage/pull/12065) needs to merge first.
#### Why I did it
`subprocess.Popen()` and `subprocess.check_output()` is used with `shell=True`, which is very dangerous for shell injection.
#### How I did it
Disable `shell=True`, enable `shell=False`
#### How to verify it
Tested on DUT, compare and verify the output between the original behavior and the new changes' behavior.
[testresults.zip](https://github.com/sonic-net/sonic-buildimage/files/9550867/testresults.zip)
- Why I did it
Fix bug: pmon report error on start up because some SKUs do not have hwsku.json
- How I did it
If hwsku.json, do not extract RJ45 port information
- How to verify it
Manual test.
Unit test.
- Why I did it
There is a hardware bug that PSU voltage threshold sysfs returns incorrect value. The workaround is to call "sensor -s" to refresh it.
- How I did it
Call "sensor -s" when the threshold value is not incorrect and PSU is "DELTA 1100"
- How to verify it
Unit test and Manual test
- Why I did it
* To support systems with dynamic port configuration
* Apply lazy initialization to faster the speed of loading platform API
- How I did it
* Add module.py to implement dynamic port configuration (aka line card model)
* Adjust chassis.py, platform.py, thermal.py, sfp.py to support dynamic port configuration
* Optimize existing code
- How to verify it
Platform regression on MSN4700, MSN3800 and MSN2700, 100% pass
Unit test covers all new changes.