Auto merge of #15284 - aneeshusa:remove-unused-windows-builders, r=larsbergstrom

Remove unused builders

These have been superseded by the windows-gnu and windows-msvc versions.
Removing them allows freeing up disk space on the Windows builders.

r? @larsbergstrom

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- [ ] `./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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etc/ci/buildbot_steps.yml

@@ -100,11 +100,6 @@ arm64:
   - bash ./etc/ci/lockfile_changed.sh
   - bash ./etc/ci/manifest_changed.sh
 
-windows-dev:
-  - ./mach build --dev
-  - ./mach test-unit
-  - ./mach build-geckolib
-
 windows-gnu-dev:
   - ./mach build --dev
   - ./mach test-unit
@@ -115,11 +110,6 @@ windows-msvc-dev:
   - mach.bat test-unit
   - mach.bat build-geckolib
 
-windows-nightly:
-  - ./mach build --release
-  - ./mach package --release
-  - ./etc/ci/upload_nightly.sh windows-gnu
-
 windows-gnu-nightly:
   - ./mach build --release
   - ./mach package --release