ci: add multi-platform tests for custom action

Author: pplmx

.github/workflows/ci.yml

@@ -13,7 +13,6 @@ jobs:
 
         strategy:
             matrix:
-                node: [ 20, 22 ]
                 os:
                     - ubuntu-latest
                     - windows-latest
@@ -29,7 +28,7 @@ jobs:
             -   name: Set up Node.js
                 uses: actions/setup-node@v4
                 with:
-                    node-version: ${{ matrix.node }}
+                    node-version: 22
                     cache: "npm"
 
             -   name: Init dependencies

.github/workflows/test_custom_action_itself.yml

@@ -9,7 +9,16 @@ on:
 
 jobs:
     test_custom_action_itself:
-        runs-on: ubuntu-latest
+        name: Test Custom Action on ${{ matrix.os }}
+
+        strategy:
+            matrix:
+                os:
+                    - ubuntu-latest
+                    - macos-latest
+
+        runs-on: ${{ matrix.os }}
+
         steps:
             -   uses: actions/checkout@v4