Fix docker build

Dockerfile

@@ -7,7 +7,7 @@ WORKDIR /go/src/app
 COPY go.mod go.sum Makefile ./
 RUN make deps
 COPY . .
-RUN OS_ARCH=${OS}/${ARCH} make release
+RUN make release
 
 FROM alpine:3.13
 
@@ -15,5 +15,6 @@ ARG OS="linux"
 ARG ARCH="amd64"
 
 WORKDIR /app
-COPY --from=builder /go/src/app/bin/driftctl_${OS}_${ARCH} /bin/driftctl
+COPY --from=builder /go/src/app/bin/driftctl_${OS}_${ARCH}/driftctl /bin/driftctl
+RUN chmod +x /bin/driftctl
 ENTRYPOINT ["/bin/driftctl"]