Add/port phsp volume integration feature

[spflueger]

Calculate the volume of arbitrary phase spaces. This code already exists in the compwa codebase and just needs to be ported to python.

[Estimated effort: 1 day]

[redeboer]

https://github.com/ComPWA/ComPWA/blob/0bf75f9fe0ec42a1a57730e187fad330a1c44e92/Physics%2FPhspVolume.cpp

[redeboer]

See also

• https://compwa-org.readthedocs.io/report/017.html
• https://ampform.readthedocs.io/en/0.14.x/usage/kinematics.html