Moffat check parameter values in `__init__`

[jecampagne]

In the PR #49 there are some missing parameter value checks

• In the __init__ GalSim checks

       if trunc == 0.0 and beta <= _beta_thr:
          raise _galsim.GalSimRangeError(
              f"Moffat profiles with beta <= {_beta_thr} must be truncated",
              beta,
              _beta_thr,
          )
       if trunc < 0.0:
          raise _galsim.GalSimRangeError("Moffat trunc must be >= 0", trunc, 0.0)

• in the MoffatCalculateSRFromHLR function Galsim checks:

  assert rm != 0.0, f"MoffatCalculateSRFromHLR: rm=={rm} should be done elsewhere"
   assert (rm > jnp.sqrt(2.0) * re), f"MoffatCalculateSRFromHLR: Cannot find a scaled radius: rm={rm}, sqrt(2)*re={jnp.sqrt(2.) * re}"

  See how to implement these checking.

[ismael-mendoza]

We are ignoring several checks in many different classes, so I'm closing this as it's not unique to the Moffat.