windows 1809 docker build pin

Author: TP Honey

.drone.yml

@@ -64,9 +64,9 @@ steps:
       - go build -o release/windows/amd64/drone-gcr.exe ./cmd/drone-gcr
       - go build -o release/windows/amd64/drone-acr.exe ./cmd/drone-acr
   - name: build docker plugin
-    image: plugins/docker
+    image: plugins/docker@sha256:f0233d950ae87ee6cb5500b2d5497fe02aa338201c0bdce2619f443fd174cfa4
     settings:
-      dockerfile: docker/docker/Dockerfile.windows.amd64.1809@sha256-61b98908250468edd34a80194cc2868cf7b30badd2ab2ff473c4497e28ddc799
+      dockerfile: docker/docker/Dockerfile.windows.amd64.1809
       repo: plugins/docker
       username:
         from_secret: docker_username