moved using namespace std in cpp file

[andreagilardoni]

No description provided.

[github-actions]

Memory usage change @ f50ddce

Board	flash	%	RAM for global variables	%
arduino:esp32:nano_nora	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_giga:giga	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_nicla:nicla_vision	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_opta:opta	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_portenta:envie_m7	N/A	N/A	N/A	N/A
arduino:renesas_portenta:portenta_c33	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:renesas_uno:unor4wifi	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
esp32:esp32:esp32	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0

Click for full report table

Board	examples/KVStoreValidation flash	%	examples/KVStoreValidation RAM for global variables	%
arduino:esp32:nano_nora	0	0.0	0	0.0
arduino:mbed_giga:giga	0	0.0	0	0.0
arduino:mbed_nicla:nicla_vision	0	0.0	0	0.0
arduino:mbed_opta:opta	0	0.0	0	0.0
arduino:mbed_portenta:envie_m7	N/A	N/A	N/A	N/A
arduino:renesas_portenta:portenta_c33	0	0.0	0	0.0
arduino:renesas_uno:unor4wifi	0	0.0	0	0.0
esp32:esp32:esp32	0	0.0	0	0.0

Click for full report CSV

Board,examples/KVStoreValidation<br>flash,%,examples/KVStoreValidation<br>RAM for global variables,%
arduino:esp32:nano_nora,0,0.0,0,0.0
arduino:mbed_giga:giga,0,0.0,0,0.0
arduino:mbed_nicla:nicla_vision,0,0.0,0,0.0
arduino:mbed_opta:opta,0,0.0,0,0.0
arduino:mbed_portenta:envie_m7,N/A,N/A,N/A,N/A
arduino:renesas_portenta:portenta_c33,0,0.0,0,0.0
arduino:renesas_uno:unor4wifi,0,0.0,0,0.0
esp32:esp32:esp32,0,0.0,0,0.0