Switch to mlugg/setup-zig@2 in CI, pin last working zig version

Author: thsackos

.github/workflows/tests-ubuntu.yml

@@ -14,14 +14,14 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - name: ⬇️ Checkout
+    - name: Checkout
       uses: actions/checkout@v4
 
     - name: (Z) Install Zig
-      uses: goto-bus-stop/setup-zig@v2
+      uses: mlugg/setup-zig@v2
       with:
-        version: master
+        version: 0.15.0-dev.565+8e72a2528
 
-    - name: ▶️ Run tests
+    - name: Run tests
       shell: bash
       run: zig build test

.github/workflows/tests-windows.yml

@@ -18,9 +18,9 @@ jobs:
       uses: actions/checkout@v4
 
     - name: (Z) Install Zig
-      uses: goto-bus-stop/setup-zig@v2
+      uses: mlugg/setup-zig@v2
       with:
-        version: master
+        version: 0.15.0-dev.565+8e72a2528
 
     - name: ▶️ Run tests
       shell: pwsh