Bump semver, concurrently, webpack and webpack-dev-server#21

dependabot[bot] wants to merge 1 commit intomastermicrosoft/TiltInteractionForMobileVisualization:masterfrom

dependabot/npm_and_yarn/semver-and-concurrently-and-webpack-and-webpack-dev-server--removedmicrosoft/TiltInteractionForMobileVisualization:dependabot/npm_and_yarn/semver-and-concurrently-and-webpack-and-webpack-dev-server--removedCopy head branch name to clipboard