partitionccl: deflake TestDropIndexWithZoneConfigCCL

A particularly adversarial goroutine schedule can cause this test to
observe the moment in time where the data is dropped but the zone config
is not. Deflake by retrying the check for the dropped zone config until
it succeeds (or times out).

Fix cockroachdb#31678.

Release note: None

pkg/ccl/partitionccl/drop_test.go

@@ -10,6 +10,7 @@ package partitionccl
 
 import (
 	"context"
+	"fmt"
 	"testing"
 
 	"github.com/pkg/errors"
@@ -124,19 +125,18 @@ func TestDropIndexWithZoneConfigCCL(t *testing.T) {
 		} else if l := 0; len(kvs) != l {
 			return errors.Errorf("expected %d key value pairs, but got %d", l, len(kvs))
 		}
+		sqlDB.QueryRow(t, "SELECT config FROM system.zones WHERE id = $1", tableDesc.ID).Scan(&buf)
+		if err := protoutil.Unmarshal(buf, cfg); err != nil {
+			return err
+		}
+		if exists := subzoneExists(cfg, 1, ""); !exists {
+			return errors.New("zone config for primary index removed after dropping secondary index")
+		}
+		for _, target := range subzones[1:] {
+			if exists := subzoneExists(cfg, target.index, target.partition); exists {
+				return fmt.Errorf(`zone config for %v still exists`, target)
+			}
+		}
 		return nil
 	})
-
-	sqlDB.QueryRow(t, "SELECT config FROM system.zones WHERE id = $1", tableDesc.ID).Scan(&buf)
-	if err := protoutil.Unmarshal(buf, cfg); err != nil {
-		t.Fatal(err)
-	}
-	if exists := subzoneExists(cfg, 1, ""); !exists {
-		t.Fatal("zone config for primary index removed after dropping secondary index")
-	}
-	for _, target := range subzones[1:] {
-		if exists := subzoneExists(cfg, target.index, target.partition); exists {
-			t.Fatalf(`zone config for %v still exists`, target)
-		}
-	}
 }