TimeService: check connection status before network/ntp time request

[pennam]

Background: a user reported a crash using ArduinoIoTCloud on ESP32 .

After a bit of research we discovered the root cause was an early NTP request due to a property initialization into the setup function. In the arduino-esp32 core the network stack is initialized when the .begin() function is called and in case of this library this happens at the first call of ArduinoCloud.update()

This PR slightly chage the behaviour of TimeSerivice adding a connection check before starting a remote time request to the connection handler or via NTP.

Doing in this way we avoid the crash reported on esp32 core and for the other platforms to submit time request that would return invalid values.

[codecov-commenter]

Codecov Report

Merging #317 (eb53f8b) into master (451d57d) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #317   +/-   ##
=======================================
  Coverage   94.87%   94.87%           
=======================================
  Files          27       27           
  Lines        1113     1113           
=======================================
  Hits         1056     1056           
  Misses         57       57           

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[github-actions]

Memory usage change @ 398bef8

Board	flash	%	RAM for global variables	%
arduino:mbed:envie_m7	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_nano:nanorp2040connect	🔺 0 - +18	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_nicla:nicla_vision	🔺 0 - +64	0.0 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkr1000	🔺 +16 - +24	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrgsm1400	🔺 +16 - +24	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrnb1500	🔺 +16 - +24	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrwan1300	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:samd:mkrwifi1010	🔺 0 - +16	0.0 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:nano_33_iot	🔺 0 - +16	0.0 - +0.01	0 - 0	0.0 - 0.0
esp32:esp32:esp32	🔺 +44 - +44	0.0 - 0.0	0 - 0	0.0 - 0.0
esp8266:esp8266:huzzah	🔺 +16 - +32	0.0 - 0.0	0 - 0	0.0 - 0.0

Click for full report table

Board	examples/ArduinoIoTCloud-Advanced flash	%	examples/ArduinoIoTCloud-Advanced RAM for global variables	%	examples/ArduinoIoTCloud-Basic flash	%	examples/ArduinoIoTCloud-Basic RAM for global variables	%	examples/utility/ArduinoIoTCloud_Travis_CI flash	%	examples/utility/ArduinoIoTCloud_Travis_CI RAM for global variables	%	examples/utility/Provisioning flash	%	examples/utility/Provisioning RAM for global variables	%	examples/utility/SelfProvisioning flash	%	examples/utility/SelfProvisioning RAM for global variables	%
arduino:mbed:envie_m7	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0
arduino:mbed_nano:nanorp2040connect	18	0.0	0	0.0	18	0.0	0	0.0	18	0.0	0	0.0	18	0.0	0	0.0	0	0.0	0	0.0
arduino:mbed_nicla:nicla_vision	0	0.0	0	0.0	64	0.01	0	0.0	64	0.01	0	0.0	0	0.0	0	0.0
arduino:samd:mkr1000	24	0.01	0	0.0	16	0.01	0	0.0	24	0.01	0	0.0	16	0.01	0	0.0
arduino:samd:mkrgsm1400	16	0.01	0	0.0	16	0.01	0	0.0	24	0.01	0	0.0	16	0.01	0	0.0
arduino:samd:mkrnb1500	16	0.01	0	0.0	16	0.01	0	0.0	24	0.01	0	0.0	16	0.01	0	0.0
arduino:samd:mkrwan1300	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0
arduino:samd:mkrwifi1010	16	0.01	0	0.0	16	0.01	0	0.0	16	0.01	0	0.0	16	0.01	0	0.0	0	0.0	0	0.0
arduino:samd:nano_33_iot	16	0.01	0	0.0	16	0.01	0	0.0	16	0.01	0	0.0	16	0.01	0	0.0	0	0.0	0	0.0
esp32:esp32:esp32	44	0.0	0	0.0	44	0.0	0	0.0	44	0.0	0	0.0
esp8266:esp8266:huzzah	32	0.0	0	0.0	16	0.0	0	0.0	16	0.0	0	0.0

Click for full report CSV

Board,examples/ArduinoIoTCloud-Advanced<br>flash,%,examples/ArduinoIoTCloud-Advanced<br>RAM for global variables,%,examples/ArduinoIoTCloud-Basic<br>flash,%,examples/ArduinoIoTCloud-Basic<br>RAM for global variables,%,examples/utility/ArduinoIoTCloud_Travis_CI<br>flash,%,examples/utility/ArduinoIoTCloud_Travis_CI<br>RAM for global variables,%,examples/utility/Provisioning<br>flash,%,examples/utility/Provisioning<br>RAM for global variables,%,examples/utility/SelfProvisioning<br>flash,%,examples/utility/SelfProvisioning<br>RAM for global variables,%
arduino:mbed:envie_m7,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0
arduino:mbed_nano:nanorp2040connect,18,0.0,0,0.0,18,0.0,0,0.0,18,0.0,0,0.0,18,0.0,0,0.0,0,0.0,0,0.0
arduino:mbed_nicla:nicla_vision,0,0.0,0,0.0,64,0.01,0,0.0,64,0.01,0,0.0,0,0.0,0,0.0,,,,
arduino:samd:mkr1000,24,0.01,0,0.0,16,0.01,0,0.0,24,0.01,0,0.0,16,0.01,0,0.0,,,,
arduino:samd:mkrgsm1400,16,0.01,0,0.0,16,0.01,0,0.0,24,0.01,0,0.0,16,0.01,0,0.0,,,,
arduino:samd:mkrnb1500,16,0.01,0,0.0,16,0.01,0,0.0,24,0.01,0,0.0,16,0.01,0,0.0,,,,
arduino:samd:mkrwan1300,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,,,,,,,,
arduino:samd:mkrwifi1010,16,0.01,0,0.0,16,0.01,0,0.0,16,0.01,0,0.0,16,0.01,0,0.0,0,0.0,0,0.0
arduino:samd:nano_33_iot,16,0.01,0,0.0,16,0.01,0,0.0,16,0.01,0,0.0,16,0.01,0,0.0,0,0.0,0,0.0
esp32:esp32:esp32,44,0.0,0,0.0,44,0.0,0,0.0,44,0.0,0,0.0,,,,,,,,
esp8266:esp8266:huzzah,32,0.0,0,0.0,16,0.0,0,0.0,16,0.0,0,0.0,,,,,,,,

[mirkokurt]

LGTM

[pennam]

TESTS:
ESP32 DEVKIT V1 ✔️
MKRWiFi 1010: ✔️
RP2040 CONNECT: ✔️
MKGGSM1400: ✔️
PORTENTA H7: ✔️
NICLA VISION: ✔️