Dependencies: Use espressif8266@^2 where HTTPClient::begin trips

It happens on an outdated Homie installation, `marvinroger/Homie@^2`. Homie/Boot/BootConfig.cpp:282:20: error: call to 'HTTPClient::begin' declared with attribute error: obsolete API, use ::begin(WiFiClient, url) 282 | _httpClient.begin(url); | ~~~~~~~~~~~~~~~~~^~~~~

Author: amotl

homie/node-homie-basic/platformio.ini

@@ -12,7 +12,7 @@
 src_dir = .
 
 [env:esp07]
-platform = espressif8266
+platform = espressif8266@^2
 board = esp07
 framework = arduino