fix compilation error

Author: jakub.pawlowski

src/registry/domain/options-sanitiser.ts

@@ -68,7 +68,7 @@ export default function optionsSanitiser(input: Input): Config {
     options.customHeadersToSkipOnWeakVersion || []
   ).map(s => s.toLowerCase());
 
-  options.port = options.port || process.env['PORT'];
+  options.port = options.port || process.env['PORT'] || 3000;
   options.timeout = options.timeout || 1000 * 60 * 2;
   options.keepAliveTimeout =
     options.keepAliveTimeout || DEFAULT_NODE_KEEPALIVE_MS;

src/types.ts

@@ -132,7 +132,7 @@ export interface Config {
   path: string;
   plugins: Record<string, (...args: unknown[]) => void>;
   pollingInterval: number;
-  port: number;
+  port: number | string;
   postRequestPayloadSize?: number;
   prefix: string;
   publishAuth?: {