RDK-42386 : Improve Unit Tests Coverage for AVInput Plugin (#164)

* RDK-42386 : Improve Unit Tests Coverage for AVInput Plugin
Reason for change: Adding L1 test cases for code coverage improvements.
Test Procedure: Run L1test to verify
Risks: Medium

Signed-off-by: Sankalp <[email protected]>

* Update test_AVInput.cpp

Added negative Test fixtures for all the APIs

* Update test_AVInput.cpp

* Update test_AVInput.cpp

* Update test_AVInput.cpp

* Update test_AVInput.cpp

* Update test_AVInput.cpp

* Update test_AVInput.cpp

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Signed-off-by: Sankalp <[email protected]>
Co-authored-by: Sankalp <[email protected]>

Author: smanes0213