The boot-assign command always panics in polkajam-repl

[bloppan]

The boot-assign command always panics when attempting to parse the queue parameter, regardless of the format used.

Steps to Reproduce

$ ./polkajam-repl                                                                                                                                                                                                                           
push-auth 0 %$null-auth foo bar                                                                                                                                                                                                                            
boot-assign 0 B

The REPL panics with:

thread 'main' panicked at crates/polkajam-repl/src/repl/context/parsing.rs:176:59:
no entry found for key

The latest version of polkajam-repl in which this worked correctly is 0.1.23.