Ignore NULs when building up the bracketed paste buffer

src/textual/_xterm_parser.py

@@ -124,7 +124,7 @@ def reissue_sequence_as_keys(reissue_sequence: str) -> None:
             character = ESC if use_prior_escape else (yield read1())
             use_prior_escape = False
 
-            if bracketed_paste:
+            if bracketed_paste and ord(character):
                 paste_buffer.append(character)
 
             self.debug_log(f"character={character!r}")