Disable QuickJS CI steps on Windows.

.github/workflows/main.yml

@@ -62,10 +62,12 @@ jobs:
       - name: Build (QuickJS runtime)
         shell: bash
         run: tests/quickjs/bootstrap.sh
+        if: runner.os != 'Windows'
 
       - name: Test (QuickJS)
         shell: bash
         run: tests/quickjs/test.sh
+        if: runner.os != 'Windows'
 
       - name: Pack
         shell: bash