fix

Signed-off-by: Yuri Shkuro <github@ysh.us>

Author: yurishkuro

Dockerfile

@@ -7,7 +7,7 @@ ENV GOPATH=/go
 RUN apk add --update --no-cache ca-certificates make git build-base mailcap
 
 WORKDIR /go/src/debug-delve
-COPY go.mod tools.go /go/src/debug-delve/
+COPY go.mod go.sum /go/src/debug-delve/
 
 # TODO: Remove s390x once go-delve adds support for it (https://github.com/go-delve/delve/issues/2883)
 # TODO: Remove ppc64le once support is released (https://github.com/go-delve/delve/issues/1564)