fix: accelerate copying code into monorepos (#3512)
fix: accelerate copying code into monorepos (#3512)

* fix: accelerate coping code into monorepos

by only globbing the directory structures once.

* Apply same acceleration when user clicks the "regenerate me" checkbox.
googleapis/repo-automation-bots,googleapis/repo-automation-bots,googleapis/repo-automation-bots,googleapis/repo-automation-bots,googleapis/repo-automation-bots