Bump remaining vulnerable dev dependencies

[cortinico]

Summary:

• Bump Rollup to a fixed 4.59.x-compatible version
• Update the lockfile for qs, flatted, follow-redirects, and basic-ftp fixed versions
• Add a scoped Mocha override so its minimatch 4.x dependency resolves to 4.2.5

Verification:

• npm run lint
• npm run prebuild
• npm run build