svelte@4 - compilerOptions.css as a boolean is deprecated

**Describe the bug**
compilerOptions.css as a boolean is deprecated. Use 'external' instead of false.

**To Reproduce**
Any compilations

**Expected behavior**
Use 'external' instead of false.

- esbuild-svelte version: latest
- esbuild version: latet
- Svelte preprocessors used (if any): yes