v0.41.9

AbstractAlgebra v0.41.9

Diff since v0.41.8

Merged pull requests:

• Add and use generic check_parent method (#1721) (@fingolfin)
• Add some argument type annotations, fix a doc typo (#1722) (@fingolfin)
• Version 0.41.9 (#1723) (@fingolfin)
• check_parent: merge MatElem, MatRingElem methods (#1724) (@fingolfin)