Update performance_benchmark.yml

Remove search path change

Author: MWSestabro

.github/workflows/performance_benchmark.yml

@@ -50,10 +50,6 @@ jobs:
                   cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DWITH_EXAMPLES=ON -DUSE_BATCH_FOR_MCC=ON -DOTEL_MATLAB_VERSION=${{ needs.get_version.outputs.version }} -DCMAKE_INSTALL_PREFIX=${{ env.OPENTELEMETRY_MATLAB_INSTALL }}
                   cmake --build build --config Release --target install
             - name: Run Benchmark
-              env:
-                 # Add the installation directory to the MATLAB Search Path by
-                 # setting the MATLABPATH environment variable.
-                 MATLABPATH: ${{ env.OPENTELEMETRY_MATLAB_INSTALL }}
               uses: matlab-actions/run-command@v2
               with:
                  command: run("opentelemetry-matlab/test/performance/runperf.m")