Add a debug build to the Makefile

Allows for step debugging a connector. More context in this discussion which provides instructions to step debug a connector 

ConduitIO/conduit#1724 (reply in thread)

Makefile

@@ -4,6 +4,10 @@ VERSION=$(shell git describe --tags --dirty --always)
 build:
 	go build -ldflags "-X 'github.com/conduitio/conduit-connector-connectorname.version=${VERSION}'" -o conduit-connector-connectorname cmd/connector/main.go
 
+.PHONY: build-debug
+build-debug:
+	go build -gcflags=all="-N -l" -ldflags="-X 'github.com/conduitio/conduit-connector-connectorname.version=${VERSION}'" -o conduit-connector-connectorname cmd/connector/main.go
+
 .PHONY: test
 test:
 	go test $(GOTEST_FLAGS) -race ./...