Update GLSK handling for AngleMonitoring

[pet-mit]

Describe the current behavior

In the angle monitoring module, re-dispatching is applied by stopping generators identified in the remedial actions linked to the angle constraints, then re-dispatching the lost generation on the other generators in the GLSK.
In order to excluded the stopped generators from the GLSK before asking powsybl to re-dispatch the lost generation, specific code is written.

Describe the expected behavior

Use powsybl's new ability to exclude generators from GLSK

Describe the motivation

Cleaner code

Extra Information

No response

[Godelaine]

merged : #1092