Build sitesearch separately

Dockerfile

@@ -2,18 +2,20 @@
 # on Go 1.16, so we build it separately.
 FROM golang:1.16 AS gobuild
 RUN go get github.com/piranha/gostatic
+RUN go get git.autistici.org/ai/webtools/cmd/sitesearch
 
 FROM debian:bullseye AS build
 RUN apt-get -q update && env DEBIAN_FRONTEND=noninteractive apt-get -qy install --no-install-recommends rsync git golang ca-certificates
 ADD . /src
 WORKDIR /src
 COPY --from=gobuild /go/bin/gostatic /usr/bin/gostatic
+COPY --from=gobuild /go/bin/sitesearch /usr/bin/sitesearch
 RUN ./scripts/lint.sh && ./scripts/update.sh
 
 FROM registry.git.autistici.org/ai3/docker/apache2-base:master
 
 COPY --from=build /src/public /var/www/autistici.org
-COPY --from=build /root/go/bin/sitesearch /usr/sbin/sitesearch
+COPY --from=gobuild /go/bin/sitesearch /usr/sbin/sitesearch
 COPY --from=build /src/index /var/lib/sitesearch/index
 COPY templates /var/lib/sitesearch/templates
 COPY docker/conf /tmp/conf