Revert "Config for new total cases field"

Going to do a calculated views field instead

This reverts commit 8354e3b8cf.

config/optional/field.storage.oc_case_provision.field_test.yml

@@ -1,20 +0,0 @@
-uuid: f90d1b9f-ee8a-4f79-ae7d-fafd4ec10cea
-langcode: en
-status: true
-dependencies:
-  module:
-    - opencase_cases
-    - opencase_entities
-id: oc_case_provision.field_test
-field_name: field_test
-entity_type: oc_case_provision
-type: entity_reference
-settings:
-  target_type: oc_actor
-module: core
-locked: false
-cardinality: 1
-translatable: true
-indexes: {  }
-persist_with_no_fields: false
-custom_storage: false