ci(arm64): fix llama.cpp build by adding googletest to CMakefile

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

backend/cpp/llama/CMakeLists.txt

@@ -83,4 +83,11 @@ target_link_libraries(${TARGET} PRIVATE common llama myclip ${CMAKE_THREAD_LIBS_
 target_compile_features(${TARGET} PRIVATE cxx_std_11)
 if(TARGET BUILD_INFO)
   add_dependencies(${TARGET} BUILD_INFO)
-endif()
+endif()
+
+include(FetchContent)
+FetchContent_Declare(
+  googletest
+  URL https://github.com/google/googletest/archive/03597a01ee50ed33e9dfd640b249b4be3799d395.zip
+)
+FetchContent_MakeAvailable(googletest)