Fix typos and remove unused variable

Author: OverloadedOrama

src/Autoload/Palettes.gd

@@ -51,7 +51,7 @@ func select_palette(palette_name: String) -> void:
 		if current_palette:
 			project.project_current_palette_name = palette_name
 	else:
-		# Attemt to find the last used palette (select if it's a global palette)
+		# Attempt to find the last used palette (select if it's a global palette)
 		var last_active_palette: String = Global.config_cache.get_value(
 			"data", "last_palette", DEFAULT_PALETTE_NAME
 		)

src/UI/Canvas/TransformationHandles.gd

@@ -387,7 +387,7 @@ func move_transform(pos: Vector2) -> void:
 	var final_pos := pos
 	if Tools.is_placing_tiles():
 		# NOTE: we don't use offset here because the [param pos] is expected to already have
-		# offseted coordinates.
+		# offsetted coordinates.
 		var grid_size := (Global.current_project.get_current_cel() as CelTileMap).get_tile_size()
 		final_pos = Tools.snap_to_rectangular_grid_boundary(pos, grid_size, Vector2.ZERO)
 	preview_transform = preview_transform.translated(final_pos)

src/UI/TilesPanel.gd

@@ -402,7 +402,6 @@ func _on_tile_button_popup_menu_index_pressed(index: int) -> void:
 			project.undo_redo.commit_action()
 	elif index == 3:  # Duplicate tile
 		var project = Global.current_project
-		var tile_cel = Global.current_project.get_current_cel()
 		var undo_data_tileset := current_tileset.serialize_undo_data()
 		var tilemap_cels: Array[CelTileMap] = []
 		var redo_data_tilemaps := {}