Add documentation examples for too-few-public-methods (#7066)

Co-authored-by: Pierre Sassoulas <pierre.sassoulas@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: 3 people

doc/data/messages/t/too-few-public-methods/bad.py

@@ -0,0 +1,7 @@
+class Worm:  # [too-few-public-methods]
+    def __init__(self, name: str, fruit_of_residence: Fruit):
+        self.name = name
+        self.fruit_of_residence = fruit_of_residence
+
+    def bore(self):
+        print(f"{self.name} is boring into {self.fruit_of_residence}")

doc/data/messages/t/too-few-public-methods/details.rst

@@ -1 +1,28 @@
-# This is a placeholder for correct code for this message.
+import dataclasses
+
+
+class Worm:
+    def __init__(self, name: str, fruit_of_residence: Fruit):
+        self.name = name
+        self.fruit_of_residence = fruit_of_residence
+
+    def bore(self):
+        print(f"{self.name} is boring into {self.fruit_of_residence}")
+
+    def wiggle(self):
+        print(f"{self.name} wiggle around wormily.")
+
+# or
+
+@dataclasses.dataclass
+class Worm:
+    name:str
+    fruit_of_residence: Fruit
+
+def bore(worm: Worm):
+    print(f"{worm.name} is boring into {worm.fruit_of_residence}")
+
+# or
+
+def bore(fruit: Fruit, worm_name: str):
+    print(f"{worm_name} is boring into {fruit}")