noopener support via custom Hugo and BlackFriday forks

.github/actions/hugo-build-action/Dockerfile

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+FROM golang:1.12-alpine
+
+LABEL repository="https://github.com/jakejarvis/hugo-build-action"
+LABEL homepage="https://jarv.is/"
+LABEL maintainer="Jake Jarvis <jake@jarv.is>"
+
+ARG HUGO_BRANCH=noopener
+# ARG HUGO_COMMIT=a28865c
+ARG HUGO_BUILD_TAGS=extended
+
+# CGO (and gcc/g++) required to build wellington/go-libsass
+ARG CGO=1
+ENV CGO_ENABLED=${CGO}
+ENV GOOS=linux
+ENV GO111MODULE=on
+
+WORKDIR /go/src/github.com/gohugoio/hugo
+
+RUN apk update && \
+    apk add --no-cache git gcc g++ musl-dev && \
+    git clone https://github.com/jakejarvis/hugo.git $GOPATH/src/github.com/gohugoio/hugo && \
+    if [ ! -z "$HUGO_BRANCH" ]; then git checkout $HUGO_BRANCH; fi && \
+    if [ ! -z "$HUGO_COMMIT" ]; then git reset --hard $HUGO_COMMIT; fi && \
+    go get github.com/magefile/mage && \
+    mage hugo && mage install
+
+RUN hugo version
+
+ENTRYPOINT ["hugo"]