use CGO_ENABLED=0 for static build

since the server executable is built outside of the docker image

buildweb.sh

 #!/bin/sh
 # This script compiles the web server application.
 set -e
-export GOBIN="$(realpath bin)"
+export GOBIN="$(realpath bin)" CGO_ENABLED=0
 cd ./src/web
 go mod download all
 go install web