NEXUS-5542: Update index task fails if one member gets a SocketTimeoutException

Similar to NEXUS-5249 but not same. This is about CASCADE operations, when one single group is being processed.

Just applied same stuff already in place from NEXUS-5249 to places doing cascade. Currently the task will fail, if any member fails, but the processing will not be interrupted, all the members will be processed. If other behaviour needed, this pull will need more.

CI
https://bamboo.zion.sonatype.com/browse/NXO-OSSF3-1