fix: stub nestjs optional modules for packaging

src/mocks/nestjs-microservices/index.ts

@@ -0,0 +1 @@
+export {};

src/mocks/nestjs-microservices/microservices-module.ts

@@ -0,0 +1 @@
+export {};

src/mocks/nestjs-websockets/index.ts

@@ -0,0 +1 @@
+export {};

src/mocks/nestjs-websockets/socket-module.ts

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+export {};