[DevEx]: Prevent unscoped `<style>` blocks with eslint rule enforce-style-attribute

[itsalaidbacklife]

Improvement Summary

We should configure the lint rule https://eslint.vuejs.org/rules/enforce-style-attribute to force all <style> blocks to be scoped except for the one in App.vue

Detailed Description

We generally require all style blocks to be scoped except for App.vue, where we put global styles. But we don't have a consistent way to enforce this. We should configure the above lint rule to require style blocks to be <style scoped> but add an override for App.vue that prevent the rule from applying to that file. Roughly this

  rules: {
    'vue-scoped-css/enforce-style-type': ['error', { allows: ['scoped', 'module'] }],
  },
  overrides: [
    {
      files: ['src/App.vue'],
      rules: {
        'vue-scoped-css/enforce-style-type': 'off',
      },
    },
  ],