rand_num_cheatcode

[Oshioke-Salaki]

Closes #2353

Introduced changes

Implemented a new cheatcode to generate a random number

Checklist

• Linked relevant issue
• Updated relevant documentation
• Added relevant tests
• Performed self-review of the code
• Added changes to CHANGELOG.md

[Draggu]

Documentation, tests, CHANGELOG.md update are missing, also you need to add relevant function on snforge_std side. Function you added should be exposed via cheatcode api (see other cheatcodes for reference) so it can be used with cheatcode in cairo.

[cptartur]

Hey, as said by @Draggu please actually integrate the cheatcode with foundry as this is not complete in the current stage.

See:
https://github.com/foundry-rs/starknet-foundry/tree/master/snforge_std/src/cheatcodes

and

https://github.com/foundry-rs/starknet-foundry/tree/master/crates/cheatnet/src/runtime_extensions/forge_runtime_extension/cheatcodes