Exported packages do not work after install

[rubensworks]

• Import default Comunica SPARQL
• Export it as zip without making any changes
• Unzip
• Install the package using npm install
• Run node bin/query.js produces the following error:

(node:18413) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
(Use `node --trace-warnings ...` to show where the warning was created)
/Users/rtaelman/Downloads/engine/bin/query.js:2
import {runArgsInProcessStatic} from "@comunica/runner-cli";
^^^^^^

SyntaxError: Cannot use import statement outside a module
    at wrapSafe (internal/modules/cjs/loader.js:1117:16)
    at Module._compile (internal/modules/cjs/loader.js:1165:27)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1221:10)
    at Module.load (internal/modules/cjs/loader.js:1050:32)
    at Function.Module._load (internal/modules/cjs/loader.js:938:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
    at internal/main/run_main_module.js:17:47

I suspect this is because the files inside bin are .js files, while they should be .ts files.
We should have a test to confirm this always works.