Update core2 requirement from 0.3.0 to 0.4.0 in /lightning#12

dependabot[bot] wants to merge 1 commit intomainvincenzopalazzo/rust-lightning:mainfrom

dependabot/cargo/lightning/core2-0.4.0vincenzopalazzo/rust-lightning:dependabot/cargo/lightning/core2-0.4.0Copy head branch name to clipboard