Try to make the library reference list in platformio.ini to look as:
lib_deps=
Blynk
Adafruit Unified Sensor
DHT sensor library
or:
lib_deps=
GitHub - blynkkk/blynk-library: Blynk library for embedded hardware. Works with Arduino, ESP8266, Raspberry Pi, Intel Edison/Galileo, LinkIt ONE, Particle Core/Photon, Energia, ARM mbed, etc.
GitHub - adafruit/Adafruit_Sensor: Common sensor library
GitHub - adafruit/DHT-sensor-library: Arduino library for DHT11, DHT22, etc Temperature & Humidity Sensors