drone: Add caching on Build, Test, Lint pipeline

.drone.yml

@@ -5,14 +5,27 @@ steps:
   image: golang:1.14
   commands:
   - go build ./...
+  volumes:
+  - name: deps
+    path: /go
 - name: Test
   image: golang:1.14
   commands:
   - go test ./...
+  volumes:
+  - name: deps
+    path: /go
 - name: Lint
   image: golangci/golangci-lint:v1.25.0
   commands:
   - golangci-lint run -v
+  volumes:
+  - name: deps
+    path: /go
+
+volumes:
+- name: deps
+  temp: {}
 
 ---
 kind: pipeline