retry ubuntu py313

Author: jmrohwer

.github/workflows/build-conda.yml

@@ -13,8 +13,8 @@ jobs:
       fail-fast: false
       matrix:
 #        os: [ubuntu-latest, windows-latest, macos-13, macos-latest]
-        os: [ubuntu-latest, windows-latest]
-        solver: [classic, libmamba]
+        os: [ubuntu-latest]
+        solver: [libmamba]
     name: Build Anaconda packages on ${{ matrix.os }} with ${{ matrix.solver }} solver
 
     steps: