fix: fixing toolbox-lite dockerfile (#2520)

Author: pjohnst5

hack/toolbox/server/Dockerfile.lite

@@ -1,5 +1,6 @@
 FROM mcr.microsoft.com/oss/go/microsoft/golang:1.21 as build
 ADD ./server/server.go /
+ADD ./server/go.mod /
 WORKDIR /
 RUN CGO_ENABLED=0 GOOS=linux go build -o server .