transition sourcerer code ownership to threat hunting investigations (e…

…lastic#184666)

## Summary

All this PR does is it changes the Sourcerer code ownership to threat
hunting investigations team.

.github/CODEOWNERS

@@ -1548,7 +1548,7 @@ x-pack/test/security_solution_cypress/cypress/tasks/expandable_flyout  @elastic/
 /x-pack/plugins/security_solution/common/cti @elastic/security-detection-engine
 /x-pack/plugins/security_solution/common/field_maps @elastic/security-detection-engine
 
-/x-pack/plugins/security_solution/public/common/components/sourcerer @elastic/security-detection-engine
+/x-pack/plugins/security_solution/public/sourcerer @elastic/security-threat-hunting-investigations
 /x-pack/plugins/security_solution/public/detection_engine/rule_creation @elastic/security-detection-engine
 /x-pack/plugins/security_solution/public/detection_engine/rule_creation_ui @elastic/security-detection-engine
 /x-pack/plugins/security_solution/public/detection_engine/rule_exceptions @elastic/security-detection-engine
@@ -1564,7 +1564,6 @@ x-pack/test/security_solution_cypress/cypress/tasks/expandable_flyout  @elastic/
 /x-pack/plugins/security_solution/server/lib/detection_engine/rule_types @elastic/security-detection-engine
 /x-pack/plugins/security_solution/server/lib/detection_engine/routes/index @elastic/security-detection-engine
 /x-pack/plugins/security_solution/server/lib/detection_engine/routes/signals @elastic/security-detection-engine
-/x-pack/plugins/security_solution/server/lib/sourcerer @elastic/security-detection-engine
 
 /x-pack/test/security_solution_cypress/cypress/e2e/detection_response/detection_engine @elastic/security-detection-engine