Colons in filenames when using llama download make them incompatible with windows.

[kylelbelcher]

Describe the bug The model ID for several of the 405B models include colons making them incompatible with windows systems.

EX: Meta-Llama3.1-405B-Instruct:bf16-mp8

OSError: [WinError 123] The filename, directory name, or volume label syntax is incorrect:

Reproduce Point llama download to Meta-Llama3.1-405B-Instruct:bf16-mp8 using Meta as the source for the model. Execute

Expected behavior File download begins