fix: copy devnet chainspec into container

Author: tjwelde

Dockerfile

@@ -63,6 +63,7 @@ RUN mkdir -p /runtime/target/release/
 COPY --from=builder /build/target/release/mashnet-node ./target/release/mashnet-node
 COPY --from=builder /build/start-node.sh ./start-node.sh
 COPY --from=builder /build/chainspec.json ./chainspec.json
+COPY --from=builder /build/chainspec.devnet.json ./chainspec.devnet.json
 
 RUN chmod a+x *.sh
 RUN ls -la .