[8.19] [Security Solution] Remove index pattern field from Sourcerer (#190113) And other sourcerer clean ups#222889

christineweng merged 4 commits intoelastic:8.19elastic/kibana:8.19from

christineweng:backport/8.19/pr-190113christineweng/kibana:backport/8.19/pr-190113Copy head branch name to clipboard