fix #15662, fix meterpreter download of utf8 filenames

[timwr]

Quick fix for #15662

Verification

List the steps needed to make sure this thing works

• Start msfconsole
• Get a native windows meterpreter session
• Run the following

meterpreter > mkdir test
Creating directory: test
meterpreter > cd test
meterpreter > edit 🔥
meterpreter > ls
Listing: C:\test
=================

Mode              Size  Type  Last modified              Name
----              ----  ----  -------------              ----
100666/rw-rw-rw-  5     fil   2021-09-13 16:16:23 +0100  🔥

meterpreter > download 🔥
[*] Downloading: 🔥 -> /metasploit-framework/🔥/🔥
[*] Downloaded 5.00 B of 5.00 B (100.0%): 🔥 -> /metasploit-framework/🔥/🔥
[*] download   : 🔥 -> /metasploit-framework/🔥/🔥

Before fix:
meterpreter > download 🔥
[-] Error running command download: Encoding::CompatibilityError incompatible character encodings: ASCII-8BIT and UTF-8

[adfoster-r7]

Github tests are failing for unrelated reasons, if you rebase against master and push it up again, they should go green 👍

[jmartin-tech]

@msjenkins-r7 test this please.

[space-r7]

Worked for me:

meterpreter > download 🔥 /Users/space/Desktop
[*] Downloading: 🔥 -> /Users/space/Desktop/🔥
[*] Downloaded 20.00 B of 20.00 B (100.0%): 🔥 -> /Users/space/Desktop/🔥
[*] download   : 🔥 -> /Users/space/Desktop/🔥

[space-r7]

Release Notes

This fixes an issue found in Meterpreter's download functionality where downloading a file with a name containing unicode characters would fail due to incompatible encoding.