Update postCreateCommand.sh

Author: devlights

.devcontainer/postCreateCommand.sh

@@ -6,3 +6,6 @@ go install golang.org/x/tools/cmd/goimports@latest
 go install github.com/go-delve/delve/cmd/dlv@latest
 
 sudo apt update && sudo apt install -y universal-ctags
+
+go mod download
+task build