Enable parallel toolkit executions by removing singleton pattern

[mrgrain]

For phase 1 we prioritized a singleton pattern as it simplified the introduction of the CliIoHost. However this creates an issue if someone wanted to do parrallel executions of the Cli i.e.

Promise.all([
    myToolkit.deploy(appA),
    myToolkit.deploy(appB)
]);

Singleton Implementation Pr:
#32708