[url_launcher_windows] Correct logging url

[anayw2001]

This CL fixes the URL being logged to be unescaped one if applicable instead of the original input URL.

Fixes #159009

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene page, which explains my responsibilities.
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• I signed the CLA.
• The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• I linked to at least one issue that this PR fixes in the description above.
• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy, or this PR is exempt from version changes.
• I updated CHANGELOG.md to add a description of the change, following repository CHANGELOG style, or this PR is exempt from CHANGELOG changes.
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• All existing and new tests are passing.

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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption, contact "@test-exemption-reviewer" in the #hackers channel in Discord (don't just cc them here, they won't see it!).

If you are not sure if you need tests, consider this rule of thumb: the purpose of a test is to make sure someone doesn't accidentally revert the fix. Ask yourself, is there anything in your PR that you feel it is important we not accidentally revert back to how it was before your fix?

Reviewers: Read the Tree Hygiene page and make sure this patch meets those guidelines before LGTMing. The test exemption team is a small volunteer group, so all reviewers should feel empowered to ask for tests, without delegating that responsibility entirely to the test exemption group.

[stuartmorgan]

Thanks for the contribution! You’ve checked boxes in the PR checklist above that are not reflected in this PR, so I’m assuming this is a work in progress and am marking it as a Draft. Please review the checklist, updating the PR as appropriate, and when the checklist reflects the state of the PR as posted please feel free to mark it as ready for review.

• I linked to at least one issue that this PR fixes in the description above.

Please make sure to complete this step as well, so that it's clear what the problem you are trying to solve is. It's not currently clear what the motivation for this change is.

[stuartmorgan]

• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy, or this PR is exempt from version changes.
• I updated CHANGELOG.md to add a description of the change, following repository CHANGELOG style, or this PR is exempt from CHANGELOG changes.
• I added new tests to check the change I am making, or this PR is test-exempt.

What are the documented version, changelog, and test exemption reasons that this PR falls under?