perf(enrich): stop searching for reachables when one is found
perf(enrich): stop searching for reachables when one is found

not extensively tested against big honking repos - but on dependency-cruiser's self cruise the amount of time it took to check for its two reachable rules was reduced from ~200ms to ~70ms (node 15.x 2.6GHz Quad-Core i7 with macOS Catalinam ~402 modules, 964 dependencies).

sverweij/dependency-cruiser,sverweij/dependency-cruiser,sverweij/dependency-cruiser,sverweij/dependency-cruiser