[Issue] Improve exception handling

[m2-assistant]

This issue is automatically created based on existing pull request: #31598: Improve exception handling

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Description (*)

When the basic exception appears - we're having mixed HTML and plain text. This PR fixes this.

Before:

❌ <pre> tags are rendered

After:

✔ <pre> tags are not rendered

Related Pull Requests

Fixed Issues (if relevant)

1. Fixes magento/magento2#<issue_number>

Manual testing scenarios (*)

1. ...
2. ...

Questions or comments

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds are green)

[m2-assistant]

Hi @engcom-November. Thank you for working on this issue.
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[engcom-November]

Hello @ihor-sviziev,

Thank you for the report and collaboration!

As this is not a bug, and not rendering <pre> tag in basic exceptions would be great.
This issue can be marked as feature request.