gh-40788: fix an error in macos ci
    
Uninstall cmake before installing dependencies. fix an error in https://
github.com/sagemath/sage/actions/runs/17527169455/job/49779204903

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actions/runner-images#12912
    
URL: #40788
Reported by: Chenxin Zhong
Reviewer(s): Chenxin Zhong, Copilot, Tobias Diez

Author: Release Manager

.github/workflows/ci-macos.yml

@@ -52,6 +52,7 @@ jobs:
 
       - name: Install dependencies
         run: |
+          brew uninstall --force cmake || true
           eval $(build/bin/sage-print-system-package-command homebrew update)
           eval $(build/bin/sage-print-system-package-command homebrew --yes --ignore-missing install $(build/bin/sage-get-system-packages homebrew _bootstrap _prereq $(build/bin/sage-package list :standard:)))
 
@@ -68,4 +69,3 @@ jobs:
         run: |
           source ./.homebrew-build-env # Needed so that runtime cython can find the dependencies
           ./sage -t --all -p4
-