[Bug] how to use svelte csf with storyshots?

[01oseluiz]

Describe the bug

I'am using svelte to describe my stories, but storyshots doesn't work with this syntax, only works with .js and .ts files.

Steps to reproduce the behavior

1. using this template https://github.com/chromaui/intro-storybook-svelte-template
2. install storyshots following what is described here: https://storybook.js.org/tutorials/intro-to-storybook/svelte/en/simple-component/
3. add "^.+\\.stories\\.svelte$": "@storybook/addon-svelte-csf/dist/cjs/jest-transform" to the jest transform map
4. run npm test storybook.test.js

Here is an example Repo: https://github.com/01oseluiz/svelte-csf-storyshots

Expected behavior

It is expected that storyshots takes a snapshot of the 'Button.stories.svelte '. But only 'Button.stories.js' is working.

Screenshots and/or logs

 console.warn
    Unexpected error while loading ./stories/Button.stories.svelte: SyntaxError: Unexpected token '<'

      at Object.warn (node_modules/@storybook/client-logger/dist/cjs/index.js:67:65)
      at node_modules/@storybook/core-client/dist/cjs/preview/loadCsf.js:92:34
          at Array.forEach (<anonymous>)
      at node_modules/@storybook/core-client/dist/cjs/preview/loadCsf.js:85:20
          at Array.forEach (<anonymous>)
      at node_modules/@storybook/core-client/dist/cjs/preview/loadCsf.js:84:12
      at ConfigApi.configure (node_modules/@storybook/client-api/dist/cjs/config_api.js:26:7)

 PASS  ./storybook.test.js
  Storyshots
    Example/Button-js
      ✓ Large (16 ms)
      ✓ Primary (4 ms)
      ✓ Secondary (4 ms)
      ✓ Small (4 **ms)**

Environment

Environment Info:

  System:
    OS: Linux 5.10 Ubuntu 20.04.3 LTS (Focal Fossa)
    CPU: (4) x64 Intel(R) Core(TM) i5-7300HQ CPU @ 2.50GHz
  Binaries:
    Node: 12.16.1 - ~/.asdf/installs/nodejs/12.16.1/bin/node
    Yarn: 1.22.10 - /home/linuxbrew/.linuxbrew/bin/yarn
    npm: 6.13.4 - ~/.asdf/installs/nodejs/12.16.1/bin/npm
  npmPackages:
    @storybook/addon-actions: ^6.3.12 => 6.3.12 
    @storybook/addon-essentials: ^6.3.12 => 6.3.12 
    @storybook/addon-links: ^6.3.12 => 6.3.12 
    @storybook/addon-svelte-csf: ^1.1.0 => 1.1.0 
    @storybook/svelte: ^6.3.12 => 6.3.12 

Additional context

Add any other context about the problem here.

[j3rem1e]

This project has a demo storybook which uses jest and storyshot. You can look at the jest configuration.