Utilize Drupal core strings for cron options

Problem/Motivation

Hi everyone,
It is a best practice to use strings from the core. By this approach the task of translation would be downsized and it does not require to add strings to database and keep it up to date manually.
Therefore, I recommend the usage of Cron options's strings which is already incorporated functions minutes, hour, day, month @count hours instead of defining new strings.

The standard core defined cron strings are available in most translation and make the module experience much closer to what user expect for.

Steps to reproduce

Install Drupal 10
Add a second language.
Enable the module
Review Cron option strings.

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes