awsdms: use custom status checker

[Jeremyyang920]

This commit switches the dms test to use a custom
status checker instead of the one from the SDK. The way the SDK checks for status changes has a likely chance of a race condition which causes it to return an error when there is really no error.

We now use a custom method to do the status checks which does an explicit status check each time the describe task api is called so we are always checking the latest result compared to the way the sdk was doing it.

Fixes: #108270
Release note: None

[cockroach-teamcity]

This change is 

[Jeremyyang920]

bors r=otan

[craig]

Build succeeded:

• Bazel Essential CI (Cockroach)

[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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error creating merge commit from af2dc5a to blathers/backport-release-22.2-108514: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 22.2.x failed. See errors above.

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