fix(config): Migrate semantic commit option to enum type (#7170)

lib/config/common.ts

lib/config/definitions.ts

lib/config/migration.spec.ts

lib/config/migration.ts

lib/config/presets/__snapshots__/index.spec.ts.snap

lib/config/presets/internal/default.ts

lib/workers/branch/commit.spec.ts

lib/workers/repository/init/config.ts

lib/workers/repository/init/semantic.spec.ts

lib/workers/repository/init/semantic.ts

lib/workers/repository/onboarding/branch/create.spec.ts

lib/workers/repository/onboarding/branch/create.ts

lib/workers/repository/onboarding/branch/rebase.ts

lib/workers/repository/updates/generate.spec.ts

lib/workers/repository/updates/generate.ts