fix: wrong location reporting in require-alt-text

[lumirlumir]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request?

Which language are you using?

CommonMark and GFM.

What did you do?

I expected a multi-line <img> tag to report the correct location, but it doesn't for the example below:

What did you expect to happen?

I expect a multi-line <img> tag to report the correct location.

Link to minimal reproducible Example

The following Markdown code may help identify the problem:

<!-- eslint markdown/require-alt-text: "error" -->

<!-- Correct -->

<img 
src="https://example.com/image.png">

<!-- Incorrect -->

<img 
 src="https://example.com/image.png">

<img 
  src="https://example.com/image.png"> 

<img 
   src="https://example.com/image.png">

What changes did you make? (Give an overview)

In this PR, I've fixed wrong location reporting in require-alt-text rule.

Related Issues

N/A

Is there anything you'd like reviewers to focus on?

N/A

[mdjermanovic]

So, html#value doesn't have leading spaces of lines, and that causes this problem.

[mdjermanovic]

LGTM, thanks!