Show installation progress when solana_version is not installed in CLI

[acheroncrypto]

Problem

During solana_version toolchain override, we set the standard I/O stream to Stdio::null in order to avoid displaying the switching process via solana-install init command. The process can take a while if the given Solana version is not installed but there is no indication of a new installation.

Solution

Anchor should only set the standard I/O stream to Stdio:null if the given solana_version is already installed. That way, users will be able to see the installation process when necessary.

[simplysabir]

Hey @acheroncrypto , can i work on this issue? i kind of understood the problem and have implementation in mind and have written that too.

[acheroncrypto]

Yeah, sure!

[simplysabir]

@acheroncrypto hey raised the PR, kindly have a look!!

#2757

[acheroncrypto]

Resolved in #2757