ci: Update test matrix

Meson 1.2 has been released and is the new baseline version for
running the test suite. Add Meson 1.1 to the list of older Meson
versions we test against.

Author: dnicolodi

.github/workflows/tests.yml

@@ -65,6 +65,9 @@ jobs:
           - os: ubuntu
             python: '3.11'
             meson: '~=1.0.0'
+          - os: ubuntu
+            python: '3.11'
+            meson: '~=1.1.0'
           # Test with Meson master branch.
           - os: ubuntu
             python: '3.11'