servo: Merge #14670 - Rename Windows nightly builders for consistency (from aneeshusa:fix-windows-nightly-builder-names); r=larsbergstrom

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Fixup for #14651. r? @larsbergstrom

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because these builders aren't used yet

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Source-Repo: https://github.com/servo/servo
Source-Revision: 5573f7cea3cc24e76501a05ff94b59c870ce7b82

servo/etc/ci/buildbot_steps.yml

@@ -121,12 +121,12 @@ windows-nightly:
   - ./mach package --release
   - ./etc/ci/upload_nightly.sh windows-gnu
 
-windows-nightly-gnu:
+windows-gnu-nightly:
   - ./mach build --release
   - ./mach package --release
   - ./etc/ci/upload_nightly.sh windows-gnu
 
-windows-nightly-msvc:
+windows-msvc-nightly:
   - mach.bat build --release
   - mach.bat package --release
   - .\etc\ci\upload_nightly.sh windows-msvc