gh-40620: Fix a typo in workflow
    
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Maybe just a typo.


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URL: #40620
Reported by: Chenxin Zhong
Reviewer(s): Copilot, Tobias Diez

Author: Release Manager

.github/workflows/ci-meson.yml

@@ -36,7 +36,7 @@ jobs:
             tests: 'new'
           # one additional editable run in pull_request, this has no effect if not pull_request
           - os: 'ubuntu'
-            python: 3.12
+            python: '3.12'
             editable: true
             tests: 'all'
           - os: windows