Fix hexdump replacement character

I guess this really should be a parameter of the function, but maybe
later.

sopass.py

@@ -28,8 +28,8 @@ def hexdump(data: bytes) -> list[str]: # We will be prefixing the lines with sig
 	offset_len = math.ceil(math.log(len(data), 16))
 	while data:
 		left_chunk, right_chunk, data = data[:8], data[8:16], data[16:]
-		left_ascii = ''.join(chr(x) if x in range(32,127) else ',' for x in left_chunk)
-		right_ascii = ''.join(chr(x) if x in range(32,127) else ',' for x in right_chunk)
+		left_ascii = ''.join(chr(x) if x in range(32,127) else '.' for x in left_chunk)
+		right_ascii = ''.join(chr(x) if x in range(32,127) else '.' for x in right_chunk)
 		offset_str = f'{offset:0{offset_len}x}'
 		line = f"{offset_str}  {left_chunk.hex(' ').ljust(23)}  {right_chunk.hex(' ').ljust(23)}  |{left_ascii.ljust(8)}{right_ascii.ljust(8)}|"
 		offset += 16