fix: Remove first dash character from filename

Author: younho9

notion2github/exporter.py

@@ -64,6 +64,8 @@ def get_notion_page(self, url, sub_path="", create_page_directory=True):
 
         if self.filename[-1] == "-":
             self.filename = self.filename[:-1]
+        if self.filename[0] == "-":
+            self.filename = self.filename[1:]
 
         self.image_number = 0