Refactored automotiveSvV1.0_fuzzer

The following are the updates to the fuzzer:
1. Added checks to the fuzzer to prevent fuzzer errors.
2. Updated the scope of the `handler` variable to avoid it going out of scope.
3. Moved `startstream` outside to ensure the proper opening of the stream.

Test: ./automotiveSvV1.0_fuzzer
Bug: 295788054

Change-Id: Ia5181ce999618cd2f6781d3681e937baa47e7071