Set Onboarding flash by default on README

[Alerymin]

I tried to flash with epsilon.onboarding_flash instead of epsilon_flash and I got the onboarding.
So for convenience I decided to change the commands in README.

[github-actions]

	.text	.rodata	.bss	.data	Total (RAM)	Total (ROM)
Base	821588 bytes	478157 bytes	226384 bytes	1816 bytes	228200 bytes	1301561 bytes
Head	821588 bytes	478157 bytes	226384 bytes	1816 bytes	228200 bytes	1301561 bytes
	+0 bytes	+0 bytes	+0 bytes	+0 bytes	+0 bytes	+0 bytes
	+0.0 %	+0.0 %	+0.0 %	+0.0 %	+0.0 %	+0.0 %

[Lisra-git]

Absolutely useless :)
By default, simulator is getting native system language to provide OOB experience without going through language/country settings, we should stick with it

[Alerymin]

No, when I flash it normally, I have to change to French and French formats
and if you reset the calculator, you don't have the onboarding.
it's not the simulator it's for flahsing on the calculator