GN build rules for four audio processing test executables
GN build rules for four audio processing test executables

click_annotate, intelligibility_proc, nonlinear_beamformer_test, and
transient_suppression_test.

BUG=webrtc:5949

Review-Url: https://codereview.webrtc.org/2267403003
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#13890}

ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc