[ws-manager] Remove trailing "Please contact support..." from error messages

[geropl]

This is a dashboard/UI concern, and should not be part of the error message.

Source:

gitpod/components/ws-manager/pkg/manager/status.go

Lines 377 to 378 in 6509092

	}
	result.Conditions.Failed += fmt.Sprintf("last backup failed: %s. Please contact support if you need the workspace data.", ds.BackupFailure)

Context: #8125 (review)

[gtsiolis]

Thanks @geropl for opening this and @sagor999 for picking this up! 🏀