Force using CPU to get e2e test working locally with macs/mps

[Sukh-P]

Pull Request

Description

When running the PVNet e2e test locally on a mac it fails with a MPS tensor datatype error, this PR forces the CPU to be used to avoid this issue (means the local test mirrors what runs in Github/through the CI)

How Has This Been Tested?

By running tests locally and checking the local error was fixed

Checklist:

• [ ] My code follows OCF's coding style guidelines
• [X] I have performed a self-review of my own code
• [ ] I have made corresponding changes to the documentation
• [X] I have added tests that prove my fix is effective or that my feature works
• [ ] I have checked my code and corrected any misspellings

[codecov[bot]]

Codecov Report

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

Project coverage is 61.39%. Comparing base (f1534d8) to head (1e8ab1d).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #169 +/- ## ======================================= Coverage 61.39% 61.39% ======================================= Files 28 28 Lines 1790 1790 ======================================= Hits 1099 1099 Misses 691 691 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.