Draft: ICSHWI-12547: Add tasks to convert extra vars into list of IOCs

Note that this is performed in the simplest and easiest to excise way as possible: an added block of tasks that can simply be removed later. The general idea is to read in all IOCs that have been deployed (using the metadata files) and update it according to the variables iocs_to_(un)deploy before following the exact same logic as before.

We could simplify this by using iocs_to_undeploy instead of creating a new list of IOCs to remove. However, I feel that this will ultimately make it somewhat more difficult to remove this at a later date, in comparison to simply removing the four added tasks.