fix(ci): macOS CI failing with python{3.7, 3.8, 3.9}

macos-latest now points to M1 runners (macos-14-arm64) which do not
support python 3.7-3.9. For these versions, use macos-12 runner.

Author: wookayin

.github/workflows/test.yml

@@ -32,6 +32,12 @@ jobs:
         exclude:
           - os: 'ubuntu-latest'
             python-version: '3.7'
+          - os: 'macos-latest'
+            python-version: '3.7'
+          - os: 'macos-latest'
+            python-version: '3.8'
+          - os: 'macos-latest'
+            python-version: '3.9'
         include:
           - os: 'ubuntu-20.04'
             python-version: '3.7'
@@ -42,6 +48,12 @@ jobs:
             NIGHTLY: nvim-linux64.tar.gz
             NVIM_BIN_PATH: nvim-linux64/bin
             EXTRACT: tar xzf
+          - os: 'macos-12'
+            python-version: '3.7'
+          - os: 'macos-12'
+            python-version: '3.8'
+          - os: 'macos-12'
+            python-version: '3.9'
           - os: 'macos-latest'
             NIGHTLY: nvim-macos-x86_64.tar.gz
             NVIM_BIN_PATH: nvim-macos-x86_64/bin