🐛 Fix two Mondoo Linux SSH checks

[mm-weber]

Fixes the props for the following checks:

• Ensure only strong ciphers are used
• Ensure that strong Key Exchange algorithms are used

[mm-weber]

Made the pattern more robust:

package('openssh-server').version.split("1:").where(_ != empty).first.split("~").where(_ != empty).first

Also added filters, so the check doesn't run if there isn't any openssh-server installed.
This case would lead to an error:

cnspec> semver(null)
x no service account configured
panic: interface conversion: interface {} is nil, not string [recovered]
	panic: interface conversion: interface {} is nil, not string

goroutine 1 [running]:
go.mondoo.com/cnquery/v11/providers-sdk/v1/upstream/health.ReportPanic({0x2b7ab10, 0x6}, {0x30754a8, 0x7}, {0x30754b0, 0x

[mm-weber]

This would need something along the lines of that: mondoohq/cnquery#5160