[build] Correct the dependencies path

[tkan145]

What

Correct the wrong dependencies path

Verification steps

• Fetch submodules

git submodule update --recursive 

• Edit Makefile as below

diff --git a/Makefile b/Makefile
index b77767fe..938b3a20 100644
--- a/Makefile
+++ b/Makefile
@@ -150,7 +150,7 @@ prove-docker: ## Test nginx inside docker
 
 runtime-image: IMAGE_NAME ?= apicast-runtime-image:latest
 runtime-image: ## Build runtime image
-       $(DOCKER) build -t $(IMAGE_NAME) $(PROJECT_PATH)
+       $(DOCKER) build -t $(IMAGE_NAME) -f Containerfile $(PROJECT_PATH)
 
 push: ## Push image to the registry
        docker tag $(IMAGE_NAME) $(REGISTRY)/$(IMAGE_NAME)

• Build runtime-image

make runtime-image

• It should produce an image without error

[gsaslis]

Looks Good To Me (LGTM)