Improve pipeline Makefile (#387)

### Description
Minor refactoring in the pipeline service's Makefile.

Changes:
* Move `pipeline` executable to the `pipeline/bin` directory.
* Remove unused targets from `pipeline/Makefile`.

pipeline/Dockerfile

@@ -16,6 +16,6 @@ FROM alpine
 #Copy certificates
 COPY --from=build /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
 # Copy our static executable.
-COPY --from=build "/app/pipeline/pipeline-app" "/pipeline"
+COPY --from=build "/app/pipeline/bin/pipeline" "/pipeline"
 # Run the binary.
 ENTRYPOINT ["/pipeline"]

pipeline/Makefile

@@ -1,21 +1,9 @@
 SHELL := /bin/bash
 
-
-## help: print this help message
-.PHONY: help
-help:
-	@echo 'Usage:'
-	@sed -n 's/^##//p' ${MAKEFILE_LIST} | column -t -s ':' |  sed -e 's/^/ /'
-
 build:
-	CGO_ENABLED=0 GOOS=linux go build -o "./pipeline-app" cmd/main.go
-	
-doc:
-	swag init -pd
-
+	CGO_ENABLED=0 GOOS=linux go build -o "./bin/pipeline" cmd/main.go
 
 test:
 	go test -v -cover ./...
 
-
-.PHONY: build doc test
+.PHONY: build test