Remove unittest and switch to pytest fully

tests/formatters/test_html_formatter.py

@@ -1,31 +1,17 @@
-import unittest
-
 from auto_archiver.core.context import ArchivingContext
 from auto_archiver.formatters.html_formatter import HtmlFormatter
 from auto_archiver.core import Metadata, Media
 
 
-class TestHTMLFormatter(unittest.TestCase):
+def test_format():
+    formatter = HtmlFormatter({})
+    metadata = Metadata().set("content", "Hello, world!").set_url('https://example.com')
 
-    def setUp(self):
-        ArchivingContext.prev_algorithm = ArchivingContext.get("hash_enricher.algorithm", "")
-        ArchivingContext.set("hash_enricher.algorithm", "SHA-256")
-        return super().setUp()
-    
-    def tearDown(self):
-        ArchivingContext.set("hash_enricher.algorithm", ArchivingContext.prev_algorithm)
-        del ArchivingContext.prev_algorithm
-        return super().tearDown()
-
-    def test_format(self):
-        formatter = HtmlFormatter({})
-        metadata = Metadata().set("content", "Hello, world!").set_url('https://example.com')
-
-        final_media = formatter.format(metadata)
-        self.assertIsInstance(final_media, Media)
-        self.assertIn(".html", final_media.filename)
-        with open (final_media.filename, "r") as f:
-            content = f.read()
-            self.assertIn("Hello, world!", content)
-        self.assertEqual("text/html", final_media.mimetype)
-        self.assertIn("SHA-256:", final_media.get('hash'))
+    final_media = formatter.format(metadata)
+    assert isinstance(final_media, Media)
+    assert ".html" in final_media.filename
+    with open (final_media.filename, "r", encoding="utf-8") as f:
+        content = f.read()
+        assert "Hello, world!" in content
+    assert final_media.mimetype == "text/html"
+    assert "SHA-256:" in final_media.get('hash')