Update documentation since hello world example changed name (#1972)

BUG=hello world example has changed name from test_hello_world_test to test_evaluate_cc_test

tensorflow/lite/micro/cortex_m_corstone_300/README.md

@@ -44,5 +44,5 @@ make -j -f tensorflow/lite/micro/tools/make/Makefile TARGET=cortex_m_corstone_30
 make -j -f tensorflow/lite/micro/tools/make/Makefile TARGET=cortex_m_corstone_300 TARGET_ARCH=cortex-m55 test_kernel_fully_connected_test
 make -j -f tensorflow/lite/micro/tools/make/Makefile OPTIMIZED_KERNEL_DIR=cmsis_nn TARGET=cortex_m_corstone_300 TARGET_ARCH=cortex-m7+fp test_kernel_fully_connected_test
 make -j -f tensorflow/lite/micro/tools/make/Makefile TARGET=cortex_m_corstone_300 TARGET_ARCH=cortex-m3 test_kernel_fully_connected_test
-make -j -f tensorflow/lite/micro/tools/make/Makefile TARGET=cortex_m_corstone_300 TARGET_ARCH=cortex-m55 BUILD_TYPE=release_with_logs TOOLCHAIN=armclang test_hello_world_test
+make -j -f tensorflow/lite/micro/tools/make/Makefile TARGET=cortex_m_corstone_300 TARGET_ARCH=cortex-m55 BUILD_TYPE=release_with_logs TOOLCHAIN=armclang test_network_tester_test
 ```