feat: add support for Vega-Lite v6 (#2205)

* feat: add support for Vega-Lite v6

* Update features.py

Fix black hook

* Black

---------

Co-authored-by: Hans Then <[email protected]>

Author: aazeeem11

folium/features.py

@@ -350,6 +350,7 @@ def render(self, **kwargs):
             3: self._embed_vegalite_v3,
             4: self._embed_vegalite_v4,
             5: self._embed_vegalite_v5,
+            6: self._embed_vegalite_v6,  # noqa
         }
 
         # Version 2 is assumed as the default, if no version is given in the schema.
@@ -367,6 +368,20 @@ def vegalite_major_version(self) -> Optional[int]:
 
         return int(schema.split("/")[-1].split(".")[0].lstrip("v"))
 
+    def _embed_vegalite_v6(self, figure: Figure, parent: TypeContainer) -> None:
+        self._vega_embed(parent=parent)
+
+        figure.header.add_child(
+            JavascriptLink("https://cdn.jsdelivr.net/npm/vega@5"), name="vega"
+        )
+        figure.header.add_child(
+            JavascriptLink("https://cdn.jsdelivr.net/npm/vega-lite@6"), name="vega-lite"
+        )
+        figure.header.add_child(
+            JavascriptLink("https://cdn.jsdelivr.net/npm/vega-embed@6"),
+            name="vega-embed",
+        )
+
     def _embed_vegalite_v5(self, figure: Figure, parent: TypeContainer) -> None:
         self._vega_embed(parent=parent)