chore: do not include module section in package

[danice]

This was causing issues as 'failed to resolve entry for package "@materializecss/materialize #455'

This entry is not needed anymore in materialize-docs when the pull request materializecss/materialize-docs#5 will be merged.

Proposed changes

remove "module": "src/index.ts" entry in package.json

Types of changes

• Bug fix (non-breaking change which fixes an issue).
• New feature (non-breaking change which adds functionality).
• Breaking change (fix or feature that would cause existing functionality to change).

Checklist:

• I have read the CONTRIBUTING document.
• My commit messages follows the conventional commit format
• My change requires a change to the documentation, and updated it accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.