[libc++][ci] Don't install wget in the Windows jobs (llvm#95215)

Nothing uses wget - only curl is used, and that's available out of the
box.

Author: mstorsjo

.github/workflows/libcxx-build-and-test.yaml

@@ -209,7 +209,7 @@ jobs:
       - uses: actions/checkout@v4
       - name: Install dependencies
         run: |
-          choco install -y ninja wget
+          choco install -y ninja
           pip install psutil
       - name: Install a current LLVM
         if: ${{ matrix.mingw != true }}