fig image build

[mathroc]

obfs4 repo has moved to gitlab.com/yawning/obfs4.git

the build was failing with this error before:

$ docker build .
Sending build context to Docker daemon 150kB
Step 1/18 : FROM golang:alpine AS go-build
---> 35cd8c8897b1
Step 2/18 : RUN apk --no-cache add --update git && go get -v git.torproject.org/pluggable-transports/obfs4.git/obfs4proxy && go get -v git.torproject.org/pluggable-transports/meek.git/meek-server && cp -rv /go/bin /usr/local/
---> Running in e6ab2ba7044f
fetch https://dl-cdn.alpinelinux.org/alpine/v3.14/main/x86_64/APKINDEX.tar.gz
fetch https://dl-cdn.alpinelinux.org/alpine/v3.14/community/x86_64/APKINDEX.tar.gz
(1/6) Installing brotli-libs (1.0.9-r5)
(2/6) Installing nghttp2-libs (1.43.0-r0)
(3/6) Installing libcurl (7.79.1-r0)
(4/6) Installing expat (2.4.1-r0)
(5/6) Installing pcre2 (10.36-r0)
(6/6) Installing git (2.32.0-r0)
Executing busybox-1.33.1-r3.trigger
OK: 19 MiB in 21 packages
go: downloading git.torproject.org/pluggable-transports/obfs4.git v0.0.0-20201207231651-40245c4a1cf2
go get: git.torproject.org/pluggable-transports/obfs4.git@v0.0.0-20201207231651-40245c4a1cf2: parsing go.mod:
module declares its path as: gitlab.com/yawning/obfs4.git
but was required as: git.torproject.org/pluggable-transports/obfs4.git
The command '/bin/sh -c apk --no-cache add --update git && go get -v git.torproject.org/pluggable-transports/obfs4.git/obfs4proxy && go get -v git.torproject.org/pluggable-transports/meek.git/meek-server && cp -rv /go/bin /usr/local/' returned a non-zero code: 1

[bluet]

LGTM

[bluet]

this fixes #7