add "make clean" tasks

Makefile

@@ -2,31 +2,40 @@ SHELL = /bin/sh
 VERSION = 0.3.0
 
 .PHONY: build build-py37 build-py38 build-py39
-.PHONE: test test-py37 test-py38 test-py39 clean
+.PHONY: test test-py37 test-py38 test-py39
+.PHONY: clean clean-py37 clean-py38 clean-py39
 
 all: test
 
 build-py37:
-	docker build -t "neo4j_arrow:${VERSION}-py37" .
+	@docker build -t "neo4j_arrow:${VERSION}-py37" .
 
 build-py38:
-	docker build -t "neo4j_arrow:${VERSION}-py38" .
+	@docker build -t "neo4j_arrow:${VERSION}-py38" .
 
 build-py39:
-	docker build -t "neo4j_arrow:${VERSION}-py39" .
+	@docker build -t "neo4j_arrow:${VERSION}-py39" .
 
 build: build-py37 build-py38 build-py39
 
 test-py37: build-py37
 	docker run --rm "neo4j_arrow:${VERSION}-py37"
 
 test-py38: build-py38
-	docker run --rm "neo4j_arrow:${VERSION}-py38"
+	@docker run --rm "neo4j_arrow:${VERSION}-py38"
 
 test-py39: build-py39
-	docker run --rm "neo4j_arrow:${VERSION}-py39"
+	@docker run --rm "neo4j_arrow:${VERSION}-py39"
 
 test: test-py37 test-py38 test-py39
 
-clean:
-	echo nop
+clean-py37:
+	@docker image rm -f "neo4j_arrow:${VERSION}-py37" 2>/dev/null
+
+clean-py38:
+	@docker image rm -f "neo4j_arrow:${VERSION}-py38" 2>/dev/null
+
+clean-py39:
+	@docker image rm -f "neo4j_arrow:${VERSION}-py39" 2>/dev/null
+
+clean: clean-py37 clean-py38 clean-py39