Import QubitDevice from devices module

[albi3ro]

Context:

In PennyLane PR #6238 we will be deprecating top level access to QubitDevice.

Description of the Change:

Imports QubitDevice from pennylane.devices instead.

Benefits:

Possible Drawbacks:

Related GitHub Issues:

[sc-71519]

[github-actions[bot]]

Hello. You may have forgotten to update the changelog! Please edit .github/CHANGELOG.md with:

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 82.70%. Comparing base (ee561f6) to head (a9a9567). Report is 1 commits behind head on master.

:exclamation: There is a different number of reports uploaded between BASE (ee561f6) and HEAD (a9a9567). Click for more details.

HEAD has 32 uploads less than BASE

| Flag | BASE (ee561f6) | HEAD (a9a9567) | |------|------|------| ||40|8|

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #897 +/- ## =========================================== - Coverage 96.60% 82.70% -13.90% =========================================== Files 212 24 -188 Lines 29301 2180 -27121 =========================================== - Hits 28306 1803 -26503 + Misses 995 377 -618 ```

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