YAML treats a leading `!` as a tag indicator, so the unquoted
`shell: ! command -v autorestic >/dev/null` was parsed as a tagged
scalar with the `!` stripped. The verify ended up running just
`command -v autorestic >/dev/null` — which exits non-zero when
autorestic is absent, the OPPOSITE of what the assertion needed.
Quoted version `"! command -v autorestic >/dev/null"` survives
parsing and gives the intended bash negation.
vh
7a2f8a1954