This is version 1.0.4, which is the latest stable release on Github (source).
PlatformIO doesn’t support beta-software as a general philosophy – however you can still arbitrarily change the package source of framework-arduinoespressif32, as documented.
[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
platform_packages =
framework-arduinoespressif32@https://github.com/espressif/arduino-esp32.git#master