Adding GStreamer test cases for Audio record and playback functionality, supports wav and flac codecs, added support in lib gstreamer sh function to handle pipelines

Signed-off-by: Nitin Nakka <nitinn@qti.qualcomm.com>

Author: nitinn22

Runner/suites/Multimedia/GSTreamer/Audio/Audio_Record_Playback/Audio_Record_Playback.yaml

@@ -0,0 +1,26 @@
+metadata:
+  name: gstreamer-audio-record-playback
+  format: "Lava-Test Test Definition 1.0"
+  description: >
+    Audio record/playback validation using GStreamer (gst-launch-1.0).
+    Tests 8 scenarios: 4 encode (2 audiotestsrc + 2 pulsesrc) + 4 decode (playback).
+    Supports WAV and FLAC formats with both synthetic audio (audiotestsrc) and hardware capture (pulsesrc).
+    Duration controlled via AUDIO_DURATION (default 10s): audiotestsrc uses num-buffers, pulsesrc uses timeout.
+  os:
+    - linux
+  scope:
+    - functional
+ 
+params:
+  AUDIO_TEST_MODE: "all"
+  AUDIO_FORMATS: "wav,flac"
+  AUDIO_DURATION: "10"
+  AUDIO_GST_DEBUG: "2"
+
+run:
+  steps:
+    - REPO_PATH="$PWD"
+    - cd Runner/suites/Multimedia/GSTreamer/Audio/Audio_Record_Playback/
+    - export AUDIO_TEST_MODE AUDIO_FORMATS AUDIO_DURATION AUDIO_GST_DEBUG
+    - ./run.sh --mode "${AUDIO_TEST_MODE}" --formats "${AUDIO_FORMATS}" --duration "${AUDIO_DURATION}" --gst-debug "${AUDIO_GST_DEBUG}" || true
+    - $REPO_PATH/Runner/utils/send-to-lava.sh Audio_Record_Playback.res || true