use an alpinelinux mirror that is actually up and has the right packages

.circleci/config.yml

@@ -18,8 +18,8 @@ jobs:
       - run:
           >
             apk add --no-cache
-            --repository https://dl-3.alpinelinux.org/alpine/edge/main
-            --repository http://dl-3.alpinelinux.org/alpine/edge/testing
+            --repository https://dl-4.alpinelinux.org/alpine/edge/main
+            --repository http://dl-4.alpinelinux.org/alpine/edge/testing
             vips-dev
       - checkout
       - restore_cache:

Dockerfile

@@ -14,8 +14,8 @@ RUN apk add \
 
 RUN apk add \
     --no-cache \
-    --repository https://dl-3.alpinelinux.org/alpine/edge/main \
-    --repository http://dl-3.alpinelinux.org/alpine/edge/testing \
+    --repository https://dl-4.alpinelinux.org/alpine/edge/main \
+    --repository http://dl-4.alpinelinux.org/alpine/edge/testing \
     vips-dev
 
 # install application dependencies
@@ -34,7 +34,7 @@ RUN yarn install --non-interactive --frozen-lockfile --production
 # copy built application to runtime image
 FROM node:10-alpine
 WORKDIR /app
-RUN apk add --no-cache --repository http://dl-3.alpinelinux.org/alpine/edge/testing \
+RUN apk add --no-cache --repository http://dl-4.alpinelinux.org/alpine/edge/testing \
     fftw vips
 COPY --from=build-stage /app/config config
 COPY --from=build-stage /app/lib lib