Bump mio from 0.8.5 to 0.8.11 in /backend#1

dependabot[bot] wants to merge 1 commit intomainsensible-hq/sse-infra:mainfrom

dependabot/cargo/backend/mio-0.8.11sensible-hq/sse-infra:dependabot/cargo/backend/mio-0.8.11Copy head branch name to clipboard