refactoring: move pretty to lib (#5551)

#5538

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Co-authored-by: a <1@1.1>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

tests/lib/test_pretty.py

@@ -2,7 +2,7 @@ import re
 
 import pytest
 
-from xonsh import pretty
+from xonsh.lib import pretty
 
 long_list = ["str"] * 30
 long_list_exp = "[" + (",\n ".join(["'str'"] * 30) + "]")

xonsh/main.py

@@ -20,8 +20,8 @@ from xonsh.imphooks import install_import_hooks
 from xonsh.jobs import ignore_sigtstp
 from xonsh.lazyasd import lazyobject
 from xonsh.lazyimps import pyghooks, pygments
+from xonsh.lib.pretty import pretty
 from xonsh.platform import HAS_PYGMENTS, ON_WINDOWS
-from xonsh.pretty import pretty
 from xonsh.shell import Shell
 from xonsh.timings import setup_timings
 from xonsh.tools import (