confirmation mail: preserve line breaks

[SnejPro]

Preserve line breaks in confirmations mails. Because addBodyText would escape the <br />-tags we need to deliver seperate html and plaintext bodys

Issue: @3389

🤖 AI (if applicable)

• The content of this PR was partly or fully generated using AI
• The content of this PR was proudly created by human mind

[SnejPro]

@Chartman123 Is there something I have to fix? For me, it does not seem as if the errors have something to do with my PR.

[Chartman123]

The errors come from a bug in Codecov action

[Chartman123]

Thanks for finding and fixing this bug :)

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