[BUG] Can't compile v3.1

[BRS3CTY]

Did you test the latest bugfix-2.0.x code?

Yes, and the problem still exists.

Bug Description

I try to compile but i've got:

Error: Unknown environment names 'mks_robin_nano_v3_usb_flash_drive'. Valid names are 'STM32F103RE_btt, DUE, mks_robin_mini, include_tree, BIGTREE_GTR_V1_0, mega1280, teensy35, BIGTREE_BTT002, STM32F103RC_btt, rumba32_mks, STM32F4, teensy31, ARMED, mks_robin_lite, melzi_optiboot, STM32F103RC_btt_USB, mks_robin, STM32F401VE_STEVAL, esp32, rumba32_f446ve, chitu_f103, SAMD51_grandcentral_m4, STM32F103RC_fysetc, STM32F103RE, STM32F407VE_black, FLYF407ZG, mks_robin_lite3, FYSETC_F6_14, LPC1768, mega2560, STM32F103CB_malyan, STM32F103RC_btt_512K, STM32F103RC, sanguino1284p, LPC1769, mks_robin_nano35, mks_robin_pro35, STM32F103VE_longer, STM32F103RE_btt_USB, rambo, at90usb1286_cdc, FYSETC_S6, jgaurora_a5s_a1, FYSETC_F6_13, STM32F103VE_GTM32, DUE_debug, STM32F103RC_btt_512K_USB, at90usb1286_dfu, STM32F7, sanguino644p, melzi, DUE_USB, BIGTREE_SKR_PRO, linux_native'

Bug Timeline

No response

Expected behavior

No response

Actual behavior

No response

Steps to Reproduce

[platformio]
src_dir = Marlin
boards_dir = buildroot/share/PlatformIO/boards
default_envs = mks_robin_nano_v3_usb_flash_drive

Version of Marlin Firmware

xxx

Printer model

Ender 3 pro

Electronics

No response

Add-ons

No response

Bed Leveling

None

Your Slicer

None

Host Software

None

Additional information & file uploads

No response