chore: Add proxy setting when docker build.

Author: ksaito1125

Makefile

@@ -3,8 +3,12 @@ NAME=$(shell dirname $@)
 VERSION=$(shell basename $@)
 TAG=aws/codebuild/$(NAME):$(VERSION)
 
+ifdef http_proxy
+BLD_OPTS=--build-arg http_proxy=$$http_proxy --build-arg https_proxy=$$https_proxy --build-arg no_proxy=$$no_proxy
+endif
+
 all: $(BUILDS)
 
 $(BUILDS):
 	cd ubuntu/$(NAME)/$(VERSION) && \
-	docker build -t $(TAG) .
+	docker build $(BLD_OPTS) -t $(TAG) .