exercises/hearing: Replace 2012-04-uchichicago commit with 2012-02-trieste

Replace the copy-paste bf93a25 (added data, 2012-03-20) from the
Chicago boot camp with the earlier 3e24204 (Added Da for Shell
example, 2012-01-30) from the Trieste boot camp [2].

[1]: https://github.com/thehackerwithin/UofCSCBC2012
[2]: https://github.com/thehackerwithin/PyTrieste

diff --git a/exercises/hearing b/exercises/hearing
index d620754f577d700ef81cdb16e3c3885f79e629f7..ba16a2adb60b3e5f09804d79843a3078b98cef0d 160000 (submodule)
--- a/exercises/hearing
+++ b/exercises/hearing
@@ -1 +1 @@
-Subproject commit d620754f577d700ef81cdb16e3c3885f79e629f7
+Subproject commit ba16a2adb60b3e5f09804d79843a3078b98cef0d