Xfields

**Changes:**
- Small bug fixes in electron cloud configuration tools

**Changes:**
- Add version number in __init__.py

**Full Changelog**: https://github.com/xsuite/xfields/compare/v0.9.2...v0.9.3

**Change:**
- Fix issue with single slice

**Full Changelog**: https://github.com/xsuite/xfields/compare/v0.9.1...v0.9.2

**Changes:**
- Added precompiled flag to force collision point to zero in BeamBeam3d

**Full Changelog**: https://github.com/xsuite/xfields/compare/v0.9.0...v0.9.1

**Changes:**
- Implementation of beamstrahlung in BeamBeamBiGaussian3D.
- Restored GPU tests that were skipped by mistake in previous releases.
- Introduce test for Gx Gy calculation in beam beam.

**Changes:**
- Use MIT Feddeeva function implementation on CPU (faster).