Enable PIO Core tests on Python 3.8

tests/test_misc.py

@@ -29,12 +29,12 @@ def test_ping_internet_ips():
         requests.get("http://%s" % host, allow_redirects=False, timeout=2)
 
 
-def test_api_internet_offline(without_internet, isolated_pio_home):
+def test_api_internet_offline(without_internet, isolated_pio_core):
     with pytest.raises(exception.InternetIsOffline):
         util.get_api_result("/stats")
 
 
-def test_api_cache(monkeypatch, isolated_pio_home):
+def test_api_cache(monkeypatch, isolated_pio_core):
     api_kwargs = {"url": "/stats", "cache_valid": "10s"}
     result = util.get_api_result(**api_kwargs)
     assert result and "boards" in result