Fix html content handling when fetching IEEE papers

[koppor]

• Fixes New cleanup for em dash jabref-koppor#286
• Closes IEEE Xplore title em dash cleanup #11078

While commenting on PR #11078, I learned that we could simply using our HtmlToLatexFormatter. I needed to teach it to understand \ in front, but it worked well.

Thanks to @InAnYan who found out where to put the cleanup. Thus, I added him to Co-authored-by.

Mandatory checks

• Change in CHANGELOG.md described in a way that is understandable for the average user (if applicable)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked developer's documentation: Is the information available and up to date? If not, I outlined it in this pull request.
• Checked documentation: Is the information available and up to date? If not, I created an issue at https://github.com/JabRef/user-documentation/issues or, even better, I submitted a pull request to the documentation repository.

[github-actions]

The build for this PR is no longer available. Please visit https://builds.jabref.org/main/ for the latest build.