Disable CGO for php-fpm-exporter build.

images/php-fpm-exporter/Dockerfile

@@ -2,6 +2,7 @@ FROM golang:latest as builder
 RUN git clone https://github.com/hipages/php-fpm_exporter.git /workspace
 WORKDIR /workspace
 RUN make deps
+ENV CGO_ENABLED=0
 RUN TARGETPLATFORM=${TARGETPLATFORM:-linux/amd64}; \
     GOOS=${TARGETPLATFORM%%/*} GOARCH=${TARGETPLATFORM#*/} go build -o php-fpm-exporter -ldflags='-extldflags "-static"' .
 
@@ -15,4 +16,4 @@ EXPOSE 9253
 COPY --from=builder /workspace/php-fpm-exporter .
 USER nonroot:nonroot
 ENTRYPOINT ["/php-fpm-exporter"]
-CMD ["server"]
+CMD ["server"]