Add marshall check for signals of maintainer list updates

[lirantal]

Ownership transfer or adding new maintainers: Any
sudden change in a package maintainers list is proposed to
be a weak link from practitioners. Practitioners would want
to know about such changes in the package dependency
graph if a package transfers the ownership or adds any new
maintainers.

Source: https://arxiv.org/pdf/2112.10165.pdf