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Validate that cronjob names are 52 characters or less
**What this PR does / why we need it**:
Right now when you create a cronjob with a name longer than 52 characters, creation will succeed but the cronjob controller will create Job objects with names longer than 63 characters. Jobs cannot have names longer than 63 characters, so the cronjob will never be able to run any jobs.
**Which issue this PR fixes** : Fixes#50850
**Special notes for your reviewer**:
**Release note**:
```release-note
Validate that cronjob names are 52 characters or less
```
Previusly github.com/robfig/cron library did not allow passing cron spec without
seconds. Previous commit updates the library, which has additional
method ParseStandard which follows the standard cron spec, iow. minute,
hour, day of month, month, day of week.
