Function When_I_set_system_time

When_I_set_system_time(now): void
When I set system time:
```
When I set system time to {int}
When I set system time to {string}
```
Parameters
- now: string | number
Returns void
Example
Change current system time to Unix epoch:
```
When I set system time to 0
```
Change current system time to 2020-02-02:
```
When I set system time to "2020-02-02"
```
Remarks
A preceding step "When I use fake timers" is required. For example:
```
When I use fake timers
  And I set system time to "2020-02-02"
```
- Defined in actions/timer.ts:105