core: <font> tag in text should reset the style to Regular

core/src/html/text_format.rs

@@ -710,6 +710,9 @@ impl FormatSpans {
                                     format.kerning = Some(false);
                                 }
                             }
+
+                            format.bold = Some(false);
+                            format.italic = Some(false);
                         }
                         b"b" => {
                             format.bold = Some(true);

tests/tests/swfs/text/style_changes_in_html/test.toml

@@ -0,0 +1,7 @@
+num_frames = 1
+
+[image_comparisons.output]
+tolerance = 0
+
+[player_options]
+with_renderer = { optional = false, sample_count = 1 }