Add -buildvcs=false to go build in Dockerfile

See docker-library/golang#415

Signed-off-by: AKP <tom@tdpain.net>

Dockerfile

@@ -1,9 +1,10 @@
-FROM golang:1-alpine as builder
+FROM golang:1.18-alpine as builder
 
 RUN mkdir /build
 ADD . /build/
 WORKDIR /build
-RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -ldflags '-extldflags "-static" -s -w' -o main github.com/codemicro/walrss/walrss
+# Go 1.18 introduced a compile-time dependency for Git unless `-buildvcs=false` is provided
+RUN CGO_ENABLED=0 GOOS=linux go build -a -buildvcs=false -installsuffix cgo -ldflags '-extldflags "-static" -s -w' -o main github.com/codemicro/walrss/walrss
 
 FROM alpine
 COPY --from=builder /build/main /