RESTRICT AUTOMERGE AudioFocusTest: Use sine1khzs40dblong.mp3 from res

Instead of loading sine1khzs40dblong.mp3 from /sdcard/test,
use the one in resources folder.
This prevents access denied errors seen in some media player
based CTS tests.

Bug: 197535999
Bug: 207088623
Test: atest CtsMediaTestCases:AudioFocusTest
Change-Id: I8bc4132a1b27d7d61ab7f5d6bc57eb24c1eb8fa8
(cherry picked from commit 587ccba9fec34fb104f851ff0fc2ea5ad6d1887d)
1 file changed