feat: add LoadTaskProcess api in containerd client

[sambhav-jain-16]

This commit aims to add an api to get the task process of the containerd client.
We have a use case where we are trying to consume the exited containers and get their exit code however the current implementation of the client doesn't expose this api.
The broader issue and use case is captured here
#3722, currently we are working on a workaround and require this api.

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[gkeesh7]

@cwangVT Do you have any more concerns with the PR ? If not could you approve this for Testing / Merging ?

[cwangVT]

@cwangVT Do you have any more concerns with the PR ? If not could you approve this for Testing / Merging ?

The test triggered and passed. The change looks good.

@bobbypage can you pls check as a second pair of eyes.

[gkeesh7]

@bobbypage could you please take a look at this PR and let us know if you have any concerns?

[gkeesh7]

@cwangVT can we merge this ?
Since you have no concerns and I see that test pipelines have passed.

[dims]

@sambhav-jain-16 are you saying that you need this for your own purpose rather than something needed for cadvisor itself?

[sambhav-jain-16]

@dims
Being an active consumer of cadvisor I felt the need for this feature. However, I feel this API can be used extensively for other purposes hence decided to add it in cadvisor itself.

[dims]

please rebase the PR

[sambhav-jain-16]

please rebase the PR

@dims done