Remove setting taint during e2e test (#621)

We're in effect testing the K8s scheduler logic in the test
by setting taints, as opposed to the actual VK itself. If we
want to make sure the taint is set, we can just observe the node
object.

Instead, bind to the pod to the VK node explicitly.

Makefile.e2e

@@ -33,9 +33,6 @@ bin/e2e/virtual-kubelet: bin/e2e
 e2e: KUBECONFIG ?= $(HOME)/.kube/config
 e2e: NAMESPACE := default
 e2e: NODE_NAME := vkubelet-mock-0
-e2e: TAINT_KEY := virtual-kubelet.io/provider
-e2e: TAINT_VALUE := mock
-e2e: TAINT_EFFECT := NoSchedule
 e2e: export VK_BUILD_TAGS += mock_provider
 e2e: e2e.clean bin/e2e/virtual-kubelet skaffold/run
 	@echo Running tests...
@@ -43,9 +40,6 @@ e2e: e2e.clean bin/e2e/virtual-kubelet skaffold/run
 		-kubeconfig=$(KUBECONFIG) \
 		-namespace=$(NAMESPACE) \
 		-node-name=$(NODE_NAME) \
-		-taint-key=$(TAINT_KEY) \
-		-taint-value=$(TAINT_VALUE) \
-		-taint-effect=$(TAINT_EFFECT)
 
 .PHONY: e2e.clean
 e2e.clean: NODE_NAME ?= vkubelet-mock-0