fix: windows save dialog extension bug

[nilaoda]

Description of Change

Fix #44277

Release Notes

Notes: Fix update file extension bug

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[ckerr]

Applying: printing.patch Patch failed at 0025 printing.patch When you have resolved this problem, run "git am --continue".

This win-x64-testing CI failure doesn't seem to have anything do to with this PR. :thinking: I'm not sure how we got here unless main was somehow broken a couple of days ago when this PR was submitted...?

@nilaoda could you please rebase this PR onto electron/electron main to see if that resolves it?

[nilaoda]

@ckerr I pulled the main branch directly without making any modifications, and I encountered the same issue when compiling with @electron/build-tools. I don’t believe this is related to my MR.🥲

Additionally, could you use Squash merge when merging this PR? This would help keep the commit list clean.

[samuelmaddock]

@nilaoda can you rebase your PR? that way it'll include a fix for some of the failing tests in CI.

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[release-clerk[bot]]

Release Notes Persisted

Fix update file extension bug

[trop[bot]]

I have automatically backported this PR to "34-x-y", please check out #44770

[trop[bot]]

I have automatically backported this PR to "33-x-y", please check out #44771