[BUG] Add overwrite to export_raw for EDF conversions

[adam2392]

PR Description

Fixes: #929

Merge checklist

Maintainer, please confirm the following before merging:

• All comments resolved
• This is not your own PR
• All CIs are happy
• PR title starts with [MRG]
• whats_new.rst is updated
• PR description includes phrase "closes <#issue-number>"

[codecov]

Codecov Report

Merging #930 (1926845) into main (4c0755c) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #930   +/-   ##
=======================================
  Coverage   94.78%   94.78%           
=======================================
  Files          23       23           
  Lines        3488     3488           
=======================================
  Hits         3306     3306           
  Misses        182      182           

Impacted Files	Coverage Δ
mne_bids/write.py	96.22% <100.00%> (ø)

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[sappelhoff]

+1 to merge when CIs are green.

Thanks Adam!

[hoechenberger]

I'll want have a look at the tests before we merge, will get back to you shortly.

[agramfort]

@hoechenberger merge if happy

🙏 @adam2392

[hoechenberger]

Pushed a tiny change, good to merge once green

[hoechenberger]

Thanks @adam2392!