Singular.jl 0.22.4 released

Today Singular.jl 0.22.4 has been released.

Diff since v0.22.3

Merged pull requests:

• create correct Singular coeffs with create_ring_from_singular_ring (#773) (@hannes14)
• update libsingular_jll to 0.42.0 (#786) (@hannes14)
• Version 0.22.4, update libsingular_julia_jll (#789) (@fingolfin)