sysutils/rubygem-bosh_cli: Make version requirement on `json_pure` less struct

[dumbbell]

Summary

After the upgrade of the json_pure gem, the BOSH CLI broke because it has a strict requirement on the version minor.

The patch simply release that strict requirement, like it is already done for other dependencies.

[antoine]

PORTREVISION has to be bumped to 1 as the package changes.

I assume you run tested it?

[dumbbell]

Bump PORTREVISION

[dumbbell]

In D9156#189177, @antoine wrote:

I assume you run tested it?

Yes, I used the tool the whole day at work.

[antoine]

looks fine, thanks!