Photoelectron tests on GPU

Description

The tests seems to run fine on GPUs, so I am activating them.

Checklist

• I have checked that my code follows the Octopus coding standards
• I have added tests for all the new features added in this request.

changed milestone to %16.0

added GPU Regression Tests labels

assigned to @nicolastd

approved this merge request

merged

mentioned in commit 9a3c5545

mentioned in merge request !2623 (closed)

added in Changelog label