Add FlakyTest annotation on correct test

This fixs commit I2065ae54d536bf7a7eabdb7a920edc76fe32aeb9

Fix: 263148628
Bug: 263213649
Test: atest WMShellFlickerTests:DragDividerToResize
Change-Id: I886e38845cdcbabb9538d5620195f04304378c88
1 file changed