[sankaku] implement 'notes' extraction (#5865)

test/results/sankaku.py

@@ -124,11 +124,13 @@ __tests__ = (
     "#class"   : sankaku.SankakuPostExtractor,
     "#options"     : {
         "tags"     : True,
+        "notes"    : True,
         "id-format": "alphanumeric",
     },
     "#sha1_content": "5e255713cbf0a8e0801dc423563c34d896bb9229",
 
     "id": "y0abGlDOr2o",
+    "notes": [],
     "tags_artist": [
         "bonocho",
     ],
@@ -149,6 +151,30 @@ __tests__ = (
     "tags_general": list,
 },
 
+{
+    "#url"     : "https://sankaku.app/posts/VAr2mjLJ2av",
+    "#comment" : "notes (#5073)",
+    "#category": ("booru", "sankaku", "post"),
+    "#class"   : sankaku.SankakuPostExtractor,
+    "#options" : {"notes": True},
+
+    "notes": [
+        {
+            "body"      : "A lonely person, is a lonely person, because he or she is lonely.",
+            "created_at": 1643733759,
+            "creator_id": 1370766,
+            "height"    : 871,
+            "id"        : 1832643,
+            "is_active" : True,
+            "post_id"   : 23688624,
+            "updated_at": 1643733759,
+            "width"     : 108,
+            "x"         : 703,
+            "y"         : 83,
+        },
+    ],
+},
+
 {
     "#url"     : "https://sankaku.app/post/show/360451",
     "#comment" : "legacy post URL",