mshtml: Use test.winehq.org over http in img_onload tests.

dlls/mshtml/tests/events.c

@@ -1854,7 +1854,7 @@ static void test_imgload(IHTMLDocument2 *doc)
     ok(V_DISPATCH(&v) == (IDispatch*)&img_onerror_obj, "V_DISPATCH(onerror) != onerrorFunc\n");
     VariantClear(&v);
 
-    str = a2bstr("https://www.winehq.org/images/winehq_logo_text.png");
+    str = a2bstr("http://test.winehq.org/tests/winehq_snapshot/index_files/winehq_logo_text.png");
     hres = IHTMLImgElement_put_src(img, str);
     ok(hres == S_OK, "put_src failed: %08x\n", hres);
     SysFreeString(str);