t6022: skip the unrepresentable file name under BusyBox

The setup shared by the --missing=print-info tests creates a file
literally named `bat"`. On native Windows the double-quote is a reserved
file name character; the MSYS2 Bash gets away with it because Cygwin
transparently mangles such names, but BusyBox' `ash` talks to the Win32
API directly and fails with "can't create bat\": Invalid argument",
taking the whole setup -- and thus all five print-info tests -- down
with it.

None of the objects exercised in this loop (HEAD~1, HEAD:foo,
HEAD:baz baz, ...) is that file, and the expected object lists are
computed dynamically, so simply not creating it under BusyBox leaves the
tests intact.

Assisted-by: Opus 4.8
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

t/t6022-rev-list-missing.sh

@@ -158,7 +158,13 @@ do
 			mkdir foo &&
 			echo bar >foo/bar &&
 			echo baz >"baz baz" &&
-			echo bat >bat\" &&
+			# Unlike MSYS2, BusyBox' native Win32 cannot create a file
+			# whose name contains the reserved '"' character; no test in
+			# this loop references it, so skip creating it under BusyBox.
+			if ! test_have_prereq BUSYBOX
+			then
+				echo bat >bat\"
+			fi &&
 			git add -A &&
 			git commit -m second &&