fix: fix storybook coverage task (#5256)

- Fixes storybook coverage command: the coverage directory path was
incorrect, but instead of failing `storybook:test --configuration=ci`,
it was hanging indefinitely.
- Switches back to `concurrently` to launch `storybook:static` and
`storybook:test` in parallel, which allows to use options to explicitly
kill `storybook:static` when `storybook:test` fails.
- Moves `storybook:test --configuration=ci` to its own command
`storybook:static:test`: used in the CI, and can be used locally to run
storybook tests without having to launch `storybook:dev` first.
- Creates command `storybook:coverage` and enables cache for this
command.
- Fixes Jest tests that were failing.
- Improves caching conditions for some tasks (for instance, no need to
invalidate Jest test cache if only Storybook story files were modified).

.github/workflows/ci-front.yaml

@@ -62,7 +62,7 @@ jobs:
       - name: Front / Write .env
         run: npx nx reset:env twenty-front
       - name: Run storybook tests
-        run: npx nx storybook:test twenty-front --configuration=ci --scope=${{ matrix.storybook_scope }}
+        run: npx nx storybook:static:test twenty-front --configuration=${{ matrix.storybook_scope }}
   front-chromatic-deployment:
     if: contains(github.event.pull_request.labels.*.name, 'run-chromatic') || github.event_name == 'push'
     needs: front-sb-build