Fix CPLEX test workflow on MacOS and Windows + other test fixes

[KilianPoirier]

Description

• Limits the numpy version to 1.x
• Fixes the failing workflow tests for CPLEX
  • Classical solutions computed using IBM ILOG CPLEX Optimization Studio are not tested on MacOS and Windows because they need a license.
  • The are still tested on a Linux environment
• Added better handling of figures in general
• Fixed angles naming convention to fit AWS braket changes + fixed pyquil compatibility
• Fixed a failing test in openqaoa/src/openqaoa-core/tests/test_workflows.py due to conversion errors
  • Changed assert into assertAlmostEqual.

Checklist

• [x] I have performed a self-review of my code.
• [x] I have commented my code and used numpy-style docstrings
• [x] I have made corresponding updates to the documentation.
• [x] My changes generate no new warnings
• [x] I have added/updated tests to make sure bugfix/feature works.
• [x] New and existing unit tests pass locally with my changes.

Type of change

• [x] Bug fix (non-breaking change which fixes an issue)