chore: Add Dependabot version-update cooldown#322

ld-repository-standards[bot] wants to merge 3 commits into

mainlaunchdarkly/flutter-client-sdk:mainfrom

ld-github-standards/add-dependabot-cooldownlaunchdarkly/flutter-client-sdk:ld-github-standards/add-dependabot-cooldownCopy head branch name to clipboard