Fix #1326 - Allow <script type="py"> tag to work as <py-script> (#1396)

The goal of this MR is to unobtrusively allow the usage of `<script type="py">`, `<script type="pyscript">` or `<script type="py-script">` tags instead of `<py-script>` for all those case where the layout in custom elements get parsed and breaks users' expectations (including our SVG based tests).

pyscriptjs/tests/integration/test_01_basic.py

@@ -9,10 +9,10 @@ class TestBasic(PyScriptTest):
     def test_pyscript_hello(self):
         self.pyscript_run(
             """
-            <py-script>
+            <script type="py">
                 import js
                 js.console.log('hello pyscript')
-            </py-script>
+            </script>
             """
         )
         assert self.console.log.lines == ["hello pyscript"]