v1.22.0

Allow env variables in graphroot and runroot
userns: make sure host id is not always 0
store: support mapped layers deletion
Cirrus: Fix matrix filter
build(deps): bump github.com/opencontainers/runc
Cirrus: Add success-accumulator task
Cirrus: Note matrix filter resolution
store: support mapped layers deletion
userns: fix host id calculation when ranges overlap
userns: simplify function
Fix leaked fd
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