Change to menu text for V2 blocks

[microbit-aimee]

Is your feature request related to a problem? Please describe.
The text under all V2 blocks needs to change from micro:bit V2 (as in example below)

Describe the solution you'd like
Text should change to micro:bit (V2) - enclosing V2 in brackets

Describe alternatives you've considered
n/a

Additional context
This aligns to our branding guidelines which request V2 is added in brackets after the word micro:bit

[pelikhan]

The purpose of this group is that indicate that those blocs are for the V2 board only. What will micro:bit (V2) indicate? It seems that (V2) is an optional argument.

[microbit-aimee]

micro:bit (V2) is intended to indicate the same information; those blocs are for V2 only - enclosing the (V2) in brackets is simply to maintain consistency with our own guidelines

[pelikhan]

Fix in #3720

[abchatra]

fixed