kubernetes: pass configuration to backend-go via env vars

kubernetes/backend-go-deployment.yaml

@@ -24,16 +24,13 @@ spec:
       - name: backend-go
         image: registry.git.rwth-aachen.de/acs/public/villas/web-backend-go:latest
         command: [ "villasweb-backend" ]
-        args: [
-          "-dbname", "villas",
-          "-dbhost", "postgres-postgresql.services",
-          "-dbuser", "$(POSTGRES_USERNAME)",
-          "-dbpass", "$(POSTGRES_PASSWORD)",
-          "-amqp", "$(AMQP_URL)",
-        ]
         env:
-        - name: GIN_MODE
+        - name: MODE
           value: release
+        - name: DB_NAME
+          value: villas
+        - name: DB_HOST
+          value: postgres-postgresql.services
         - name: RABBITMQ_USERNAME
           valueFrom:
             secretKeyRef:
@@ -44,12 +41,12 @@ spec:
             secretKeyRef:
               name: rabbitmq-credentials
               key: password
-        - name: POSTGRES_USERNAME
+        - name: DB_USER
           valueFrom:
             secretKeyRef:
               name: postgres-credentials
               key: username
-        - name: POSTGRES_PASSWORD
+        - name: DB_PASS
           valueFrom:
             secretKeyRef:
               name: postgres-credentials