Backport !5605 - Proto: allow to pay to increase the contract storage
Context
!5605 (merged) is required in protocol Kathmandu. Cherry-picked commit from it using the following commands.
$ git checkout -b proto-k-backport-5605
$ git cherry-pick fddeda03c708f0e35700733c60b7ce222d3269bf
Resolved conflict in docs/protocols/alpha.rst.
Manually testing the MR
Check CI.