Update htk requirements

This change updates the helm-toolkit path in each chart as part
of the move to helm v3. This is due to a lack of helm serve.

Change-Id: I011e282616bf0b5a5c72c1db185c70d8c721695e

openvswitch/requirements.yaml

@@ -13,6 +13,6 @@
 ---
 dependencies:
   - name: helm-toolkit
-    repository: http://localhost:8879/charts
+    repository: file://../helm-toolkit
     version: ">= 0.1.0"
 ...