Program security - PDA sharing lesson updated

[0xCipherCoder]

Problem

Summary of Changes

• Updated code snippets with the latest anchor version
• Fixed content with updated version changes
• Fixed grammar and styling
• Fixed as per guidelines

Fixes #

Unboxed PRs
Starter - solana-developers/pda-sharing#1
Solution - solana-developers/pda-sharing#2

[mikemaccana]

Great work, some minor changes but not many, we should be able to get this in immediately once done.

[0xCipherCoder]

Great work, some minor changes but not many, we should be able to get this in immediately once done.

Thanks! @mikemaccana I have updated code as per comment and respective Unbox PRs in both starter and solution branch.

[mikemaccana]

Thanks @0xCipherCoder . You've won this one too.

[0xCipherCoder]

Thanks! @mikemaccana