moved using namespace std in cpp file

src/kvstore/implementation/ESP32.cpp

@@ -13,6 +13,8 @@
 #include "nvs.h"
 #include "nvs_flash.h"
 
+using namespace std;
+
 bool ESP32KVStore::begin(const char* name, bool readOnly, const char* partition_label) {
     if(_started){
         return false;

src/kvstore/implementation/ESP32.h

@@ -13,8 +13,6 @@
 #include <Arduino.h>
 #include <string>
 
-using namespace std;
-
 constexpr char DEFAULT_KVSTORE_NAME[] = "arduino";
 
 class ESP32KVStore: public KVStoreInterface {

src/kvstore/implementation/Nina.cpp

@@ -12,6 +12,8 @@
 
 #include "Nina.h"
 
+using namespace std;
+
 bool NinaKVStore::begin(const char* name, bool readOnly, const char* partitionLabel) {
     WiFiDrv::wifiDriverInit();
 

src/kvstore/implementation/Nina.h

@@ -13,8 +13,6 @@
 
 #include <WiFi.h>
 
-using namespace std;
-
 const char DEFAULT_KVSTORE_NAME[] = "arduino";
 
 class NinaKVStore: public KVStoreInterface {

src/kvstore/implementation/UnoR4.cpp

@@ -11,6 +11,8 @@
 #if defined(ARDUINO_UNOR4_WIFI)
 #include "UnoR4.h"
 
+using namespace std;
+
 bool Unor4KVStore::begin(const char* name, bool readOnly, const char* partitionLabel) {
     this->name = name;
     string res = "";

src/kvstore/implementation/UnoR4.h

@@ -14,8 +14,6 @@
 #include <Modem.h>
 #include <string>
 
-using namespace std;
-
 constexpr char DEFAULT_KVSTORE_NAME[] = "arduino";
 
 class Unor4KVStore: public KVStoreInterface {