feat: add svelte/no-trailing-spaces rule

[ota-meshi]

This PR adds svelte/no-trailing-spaces rule that extends no-trailing-spaces rule.
close #233

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Latest commit: 6e6e173

The changes in this PR will be included in the next version bump.

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Name	Type
eslint-plugin-svelte	Minor

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[JounQin]

I'm not quite sure to understand why the built-in no-trailing-spaces rules does not work with this?

We should have already marked this following as comments? Then why ignoreComments: true does not work as expected?

<!-- @component
  InlineButton - A button that blends in with paragraph  
  styles, but is interactive.
-->

[ota-meshi]

svelte-eslint-parser does not treat HTML comments as comment tokens. This is done in order to prevent false positives in ESLint's rules for processing comments (prefix behaves on the assumption that it is 2 characters, but there are actually 4 characters in HTML comments). If we treat HTML comments as comment tokens, auto-fix will break your source code.

[JounQin]

In eslint-mdx@v1, we are replacing HTML comments into JSX comments with same length of * tokens:

<!-- old -->
<!-- comment -->

<!-- new -->
{/** comment **}

I don't know if it is a good approach, but it works perfect in eslint-mdx@v1

[ota-meshi]

I didn't come up with that hack. It might be worth trying, but it might be difficult as it involves breaking changes.

[JounQin]

Can we add some TODO comments to remind us?

[ota-meshi]

It might make more sense to open an issue in the svelte-eslint-parser repository since it's a change in svelte-eslint-parser.

[JounQin]

@ota-meshi just raised sveltejs/svelte-eslint-parser#202