Add lower-to-higher precision conversion in _convert_timestamp

[rwader-swi]

Closes #

Proposed Changes

Currently the _convert_timestamp util only supports higher precision to lower precision time conversion. Some of the usecases might need the opposite, and instead of writing on our own we wish to use this already present utility. In my usecase the data is in floating point as seconds which I might want to convert to nanoseconds or other precision. So did some small changes.

Checklist

• [ ] CHANGELOG.md updated
• [X] Rebased/mergeable
• [ ] A test has been added if appropriate
• [ ] pytest tests completes successfully
• [X] Commit messages are conventional
• [ ] Sign CLA (if not already signed)

[bednar]

This PR has been closed because it has not had recent activity. Please reopen if this PR is still important to you and you want to continue with them.