Style: Trim trailing whitespace and ensure newline at EOF

Found by apply the file_format checks again via #91597.

modules/gdscript/tests/scripts/lsp/local_variables.gd

@@ -9,7 +9,7 @@ func test_member() -> void:
 	#   ^^^^ test -> test
 	test += 3
 	#<^^ -> test
-	member += 5	
+	member += 5
 	#<^^^^ -> member
 	test = return_arg(test)
 	#  |              ^^^^ -> test
@@ -22,4 +22,4 @@ func return_arg(arg: int) -> int:
 	arg += 2
 	#<^ -> arg
 	return arg
-	#      ^^^ -> arg
+	#      ^^^ -> arg