added tests for all formatters; stylecheck workflow now also checks in tests now

html_to_django/formatters/attr_formatter.py

@@ -3,6 +3,6 @@ from bs4 import BeautifulSoup
 
 def format(soup: BeautifulSoup) -> None:
     for element in soup.find_all(attrs={"dj-attr": True}):
-        tag, value = element.get("dj-attr").split(";")
-        element[tag] = f"{{{{ {value} }}}}"
+        for tag, value in [attr.split(";") for attr in element["dj-attr"].split("~")]:
+            element[tag] = f"{{{{ {value} }}}}"
         del element.attrs["dj-attr"]