Function ttlLoginRule

ttlLoginRule(ttl): LoginConfigSimpleRule
Creates a login rule which represents "this rule will be valid for ttl seconds", where ttl is the input to the function. Goes great with the functions for representing time. E.g.,
```
ttlLoginRule(30) // Valid for 30 seconds
ttlLoginRule(minutes(10)) // Valid for 10 minutes
ttlLoginRule(days(2)) // Valid for 2 days
...
```
Parameters
- ttl: number
  for how long (in seconds) the rule is valid.
Returns LoginConfigSimpleRule