fix: type error during svelte init

[pckilgore]

On a system without prettier-plugin-svelte with the last patch:

> function createSvelteParsers() {
...     try {
...         var { parsers } = require('prettier-plugin-svelte');
...     } catch {
...         return {}
...     }
...     return { parsers }
... }
undefined
> console.log({ ...createSvelteParsers().parsers.svelte })
Uncaught TypeError: Cannot read properties of undefined (reading 'svelte')

This PR fixes that.

[pckilgore]

I see this was fixed further up the call stack.