Migrate to yarn v4

Use yarn PnP which forces us to install some more explicit dependencies.

Change-Id: Ib35c5c71a37081c98778937bde5a23bf997dd54c

Dockerfile

@@ -4,10 +4,16 @@ LABEL org.opencontainers.image.url=https://github.com/Awesome-Technologies/synap
 
 WORKDIR /src
 
-COPY . /src
-RUN yarn --network-timeout=300000 install --immutable
-RUN yarn build
+# Copy .yarn directory to the working directory (must be on a separate line!)
+# Use https://docs.docker.com/engine/reference/builder/#copy---parents when available
+COPY .yarn .yarn
+COPY package.json .yarnrc.yml yarn.lock ./
 
+# Disable telemetry and install packages
+RUN yarn config set enableTelemetry 0 && yarn install --immutable --network-timeout=300000
+
+COPY . /src
+RUN yarn build
 
 # App
 FROM nginx:stable-alpine