refactor: move updateContainerStoppedLabel to containerutil

[davidhsingyuchen]

PR is a blocker of refactoring container stop and container start as part of #1680.

Thought process:

1. I removed Container from the function name to avoid stuttering with the package name (i.e., containerutil). Also, one of the parameters is container containerd.Container, so the semantics should be already clear.
2. I noticed that stopped bool is a bit misleading as it seems to say whether the container is stopped, but the point is to convey whether the container is explicitly stopped so that containerd can decide if the container should be restarted. As a result, I renamed the parameter and the function accordingly.

Please let me know if I should do this in a follow-up PR instead, or it just doesn't make sense and shouldn't be done at all, thanks!

Signed-off-by: Hsing-Yu (David) Chen davidhsingyuchen@gmail.com

[Zheaoli]

LGTM

[Laitr0n]

We're doing some works that are the same. I refactored the container start in PR #1864, but I discovered that the CL is enormous, which made it difficult for reviewers to review. So,I am breaking it down into multiple PRs such as #1882, #1891 and so on. Once one PR is merged, I will proceed with the next one.

[davidhsingyuchen]

We're doing some works that are the same.

Oh I see, I checked the open PRs yesterday, and it seems that #1864 was just reopened today. I will stop creating PRs for those items.

Once one PR is merged, I will proceed with the next one.

Maybe they can be done in parallel as the refactoring blocks not only container start but also other commands. I think the point is to break the giant PR into smaller/independent ones instead of doing them serially.

[Laitr0n]

SGTM.
I will open more pr that has no dependent with another at the same time.