[Smartswitch] Host container differentiation for sensor commands

[gpunathilell]

Description

Differentiate commands being executed in host and container seperately for some smartswitch specific functions,
sensord commands can only be executed inside hte pmon docker container, so these commands need to differentiate between host and container execution

Motivation and Context

This is done because these functions are called from inside the pmon docker during chassis command execution and from the host directly during reboot command execution

How Has This Been Tested?

tests/module_base_test.py::TestModuleBase::test_module_base PASSED       [  2%]
tests/module_base_test.py::TestModuleBase::test_is_container_detection PASSED [  2%]
tests/module_base_test.py::TestModuleBase::test_sensors PASSED           [  2%]
tests/module_base_test.py::TestModuleBase::test_pci_entry_state_db PASSED [  2%]
tests/module_base_test.py::TestModuleBase::test_file_operation_lock PASSED [  2%]
tests/module_base_test.py::TestModuleBase::test_pci_operation_lock PASSED [  2%]
tests/module_base_test.py::TestModuleBase::test_sensord_operation_lock PASSED [  3%]
tests/module_base_test.py::TestModuleBase::test_handle_pci_removal PASSED [  3%]
tests/module_base_test.py::TestModuleBase::test_handle_pci_rescan PASSED [  3%]
tests/module_base_test.py::TestModuleBase::test_handle_sensor_removal PASSED [  3%]
tests/module_base_test.py::TestModuleBase::test_handle_sensor_addition PASSED [  3%]
tests/module_base_test.py::TestModuleBase::test_module_pre_shutdown PASSED [  3%]
tests/module_base_test.py::TestModuleBase::test_module_post_startup PASSED [  3%]

Manual test with:
reboot -d DPU0
and config chassis modules startup DPU0

Additional Information (Optional)

[mssonicbld]

/azp run

[azure-pipelines]

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[mssonicbld]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[mssonicbld]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[gpunathilell]

@vvolam and @rameshraghupathy please review

[Copilot]

Pull Request Overview

This PR adds host/container differentiation for sensor commands in ModuleBase class for smartswitch functionality. The changes enable sensord commands to be executed properly both when called from within the pmon docker container and when called from the host system during different operations.

• Introduces host detection mechanism using the presence of /.dockerenv file
• Modifies sensor handling methods to use subprocess calls with docker exec when running on host
• Updates command execution to differentiate between host and container environments

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
sonic_platform_base/module_base.py	Adds _is_host() method and modifies sensor removal/addition methods to use subprocess calls with docker exec prefixes when running on host
tests/module_base_test.py	Updates test cases to cover both host and container execution scenarios with proper mocking of subprocess calls

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[mssonicbld]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[mssonicbld]

Cherry-pick PR to msft-202506: Azure/sonic-platform-common.msft#111