Bare Imports fail when using CJS format

[clintwood]

Describe the bug
When using a bare import in a component script (also with script in module context as in thsi example) there are no specifiers on the node at this line which causes this error: TypeError: Cannot read property 'type' of undefined

To Reproduce
a.js:

// any code here - empty is fine too

Component.svelte:

<script context="module">
  import './a';
</script>

compile.js:

const { readFileSync } = require('fs');
const svelte = require('svelte/compiler');

const source = readFileSync('./Component.svelte', 'utf8');

const result = svelte.compile(source, {
  format: 'cjs',
});

console.log(result);

Expected behavior
Should compile and generate require('./a.js'); in the example provided above.

Stacktrace

/project-dir/node_modules/svelte/compiler.js:21095
	                id: node.specifiers[0].type === 'ImportNamespaceSpecifier'
	                                       ^

TypeError: Cannot read property 'type' of undefined
    at /project-dir/node_modules/svelte/compiler.js:21095:41
    at Array.map (<anonymous>)
    at cjs (/project-dir/node_modules/svelte/compiler.js:21090:36)
    at create_module (/project-dir/node_modules/svelte/compiler.js:21002:17)
    at Component.generate (/project-dir/node_modules/svelte/compiler.js:24900:14)
    at Object.compile (/project-dir/node_modules/svelte/compiler.js:25965:23)
    at Object.<anonymous> (/project-dir/compile.js:6:23)
    at Module._compile (internal/modules/cjs/loader.js:1121:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1160:10)
    at Module.load (internal/modules/cjs/loader.js:976:32)

Information about your Svelte project:
Not relevant but I'm using Svelte v3.16.0

Severity
Blocking - I'm using Jest for testing which requires cjs format with jest-transform-svelte which forces cjs format which breaks on compile when using a bare import.

[Conduitry]

Presumably, we just need to handle the case here of node.specifiers being an empty array, and return only the require().

[clintwood]

Wow thank you for the swift response and PR already!

[Conduitry]

Fixed in 3.16.1.