cargo-dependabot-if-necessary

For most of my crates i would love to use dependabots "increase-if-necessary" strategy, unfortunately that isn't supported.

See dependabot-core!4009 for more details

This little tool updates or generate a dependabot file with the cargo ecosystems version ignores in a way to mimic the increase-if-necessary strategy.

See this crates own dependabot.yml for an example of the output.