Update verifiable randomness functions.md

[adpthegreat]

Summary of Changes

• Updated link to starter code from https://github.com/Unboxed/-Software/michael-burry-escrow To https://github.com/solana-developers/burry-escrow

• Renamed escrowState to Escrow in the ts tests

• Renamed VrfClientState to VrfClient

• Corrected solUsedSwitchBoardFeed to solUsdSwitchBoardFeed

• Renamed escrow_amt to escrow_amount

• Renamed all variables with "ix" to Instruction

• Renamed tx to transaction in the burry-escrow.ts

Used anchors INITSPACE ,instead of std::mem::size also replaced the magic number 8 with an anchor discriminator variable

• Fixed some grammar errors

• Removed unnecessary awaits in test

• Changed the type for unlock_price from f64 to u64

• edited subheadings from #### to ### for consistency

-Renamed VRF_STATE_SEED TO VRF_STATE

• Updated assertions comparing numbers in tests to use .eq() method in place of ===

• changed anchor.BN to BN

• Wrapped solPrice with BN

• renamed e to error for more clarity

• Ran code to make sure tests work accordingly

• Created PRs in https://github.com/solana-developers/burry-escrow to add branches vrf and vrf-challenge-solution as well as fixes to burry escrow