Alias with payload: `I/O operation on closed file` and `Bad file descriptor` about xonsh

[anki-code]

@gforsyth @jnoortheen This is regress. I traced this and this issue was made in 0.13.0:

• 013fa76 refactor(amalgamate): remove amalgamation (#4858)

Let's investigate what is wrong because I think this could follow to solving bunch of other issues (around PTK, etc).

[anki-code]

I found that the issue appears if we switch off the amalgamation.

docker run --rm -it xonsh/xonsh:slim bash
apt update && apt install -y git
# v0.12.6
pip install --force-reinstall git+https://github.com/xonsh/xonsh@cbf23e60fba9c6479d23cff03884572a776e6f1d
xonsh
# working

XONSH_NO_AMALGAMATE=1 xonsh
# not working  # amalgamation was the glue :)

[anki-code]

Trying to catch the difference:

# Amalgamate
XONSH_NO_AMALGAMATE= xonsh --no-rc 

import sys
@aliases.register('tst')
def _test(args, i, o, e):
    print('func', i, o, e)
    print('sys', sys.stdout, sys.stderr)
    __import__('time').sleep(1)
tst
tst
tst
tst
# func None <_io.TextIOWrapper name=7 encoding='utf-8'> <_io.TextIOWrapper name=9 encoding='utf-8'>
# sys <xonsh.procs.__amalgam__.FileThreadDispatcher object at 0x101815d60> <xonsh.procs.__amalgam__.FileThreadDispatcher object at 0x101815dc0>

# No Amalgamate
XONSH_NO_AMALGAMATE=1 xonsh --no-rc 

import sys
@aliases.register('tst')
def _test(args, i, o, e):
    print('func', i, o, e)
    print('sys', sys.stdout, sys.stderr)
    __import__('time').sleep(1)

# first run
tst
# func None <_io.TextIOWrapper name=7 encoding='utf-8'> <_io.TextIOWrapper name=9 encoding='utf-8'>
# sys <xonsh.procs.proxies.FileThreadDispatcher object at 0x1051c4680> <xonsh.procs.proxies.FileThreadDispatcher object at 0x1051c46e0>

# second run
tst
# func None <_io.TextIOWrapper name=7 encoding='utf-8'> <_io.TextIOWrapper name=9 encoding='utf-8'>
# IO ERROR

Only one difference: xonsh.procs.proxies.FileThreadDispatcher vs xonsh.procs.__amalgam__.FileThreadDispatcher.

UPD: I traced it further and amalgamation of xonsh.procs.proxies is the key.