[Rule Tuning] Remove empty technique array logic

[brokensound77]

Related to elastic/kibana#87546
Related to #812

7.11 required technique to at least contain an empty array when techniques were not defined. Once Kibana updates the schema to make the field optional, we should strip it from all of the rules:

[brokensound77]

#828 removed the empty array from rules and inserts them dynamically, so this is no longer required. We should remove the dynamic insertion though, once the schema no longer requires it (updating title)

[brokensound77]

Kibana PR removes the need for the empty technique array. Will remove the build-time insertion logic alongside upcoming OOB release code updates.

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[brokensound77]

I think we are just going to leave it as is