Revert "Merge branch '230437-usage-data-optimize-counts-terraform_reports' into 'master'"

This reverts merge request !37498

changelogs/unreleased/230437-usage-data-optimize-counts-terraform_reports.yml

----
-title: Optimize counts.terraform_reports usage ping counter
-merge_request: 37498
-author:
-type: performance

db/post_migrate/20200811211536_add_index_to_ci_job_artifacts_for_terraform_reports_id.rb

-# frozen_string_literal: true
-
-class AddIndexToCiJobArtifactsForTerraformReportsId < ActiveRecord::Migration[6.0]
-  include Gitlab::Database::MigrationHelpers
-
-  DOWNTIME = false
-  INDEX_NAME = 'index_ci_job_artifacts_id_for_terraform_reports'
-
-  disable_ddl_transaction!
-
-  def up
-    add_concurrent_index :ci_job_artifacts, :id, where: 'file_type = 18', name: INDEX_NAME
-  end
-
-  def down
-    remove_concurrent_index_by_name :ci_job_artifacts, INDEX_NAME
-  end
-end

db/schema_migrations/20200811211536

-d4ea24092289f6dba294c502b8ce89748165973fb2d7989fa7615433599a0c0c
\ No newline at end of file

db/structure.sql

@@ -19198,8 +19198,6 @@ CREATE UNIQUE INDEX index_ci_instance_variables_on_key ON public.ci_instance_var
 
 CREATE INDEX index_ci_job_artifacts_for_terraform_reports ON public.ci_job_artifacts USING btree (project_id, id) WHERE (file_type = 18);
 
-CREATE INDEX index_ci_job_artifacts_id_for_terraform_reports ON public.ci_job_artifacts USING btree (id) WHERE (file_type = 18);
-
 CREATE INDEX index_ci_job_artifacts_on_expire_at_and_job_id ON public.ci_job_artifacts USING btree (expire_at, job_id);
 
 CREATE INDEX index_ci_job_artifacts_on_file_store ON public.ci_job_artifacts USING btree (file_store);