Enhance bug report template with file upload option (#46015)

<!-- Enter a brief description/summary of your PR here. What does it
fix/what does it change/how was it tested (even manually, if necessary)?
-->
## Summary of the Pull Request

Adds an upload field for the bug report ZIP-file to the bug report issue
template.

<img width="982" height="157" alt="image"
src="https://github.com/user-attachments/assets/5b7175d7-eacf-4748-93e8-304a027de005"
/>

## PR Checklist

<!-- - [ ] Closes: #yyy (add separate lines for additional resolved
issues) -->
- [x] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected

---------

Co-authored-by: Niels Laute <niels.laute@live.nl>

.github/actions/spell-check/expect.txt

@@ -129,6 +129,7 @@ bthprops
 bti
 BTNFACE
 bugreport
+bugreportfile
 BUILDARCH
 BUILDNUMBER
 buildtransitive