ci: Decommission macOS 13

Author: nikitabelonogov

.github/workflows/tests.yml

@@ -11,7 +11,6 @@ jobs:
     strategy:
       matrix:
         os:
-          - "macos-13" # Intel x64
           - "macos-15" # Apple M1
           - "macos-26" # Apple M1
     runs-on: ${{ matrix.os }}