Mysql error upgrading from 9.5 to 10.1

I get this error after upgrade 9.5 to 10.1:

==> production.log <==

ActionView::Template::Error (Mysql2::Error: Illegal mix of collations (utf8_general_ci,IMPLICIT) and (utf8_unicode_ci,IMPLICIT) for operation '=': SELECT  `events`.* FROM `events` INNER JOIN `push_event_payloads` ON `push_event_payloads`.`event_id` = `events`.`id` WHERE `events`.`action` IN (5) AND (NOT EXISTS (SELECT 1 FROM `merge_requests` WHERE `merge_requests`.`deleted_at` IS NULL AND (merge_requests.source_project_id = events.project_id) AND (merge_requests.source_branch = push_event_payloads.ref))) AND `push_event_payloads`.`action` IN (2, 0) AND `push_event_payloads`.`ref_type` = 0 AND `events`.`id` = 57922 LIMIT 1):
    1: - event = last_push_event
    2: - if event && show_last_push_widget?(event)
    3:   .row-content-block.top-block.hidden-xs.white
    4:     .event-last-push
  config/initializers/connection_fix.rb:20:in `execute'
  app/services/users/last_push_event_service.rb:62:in `find_event_in_database'
  app/services/users/last_push_event_service.rb:47:in `find_cached_event'
  app/services/users/last_push_event_service.rb:30:in `last_event_for_user'
  app/models/user.rb:687:in `recent_push'
  app/helpers/projects_helper.rb:143:in `last_push_event'
  app/views/projects/_last_push.html.haml:1:in `_app_views_projects__last_push_html_haml__3983927651486954531_47312233557260'
  app/views/dashboard/projects/index.html.haml:10:in `_app_views_dashboard_projects_index_html_haml__3285765044640251629_47312234872000'
  app/controllers/dashboard/projects_controller.rb:10:in `index'
  app/controllers/root_controller.rb:18:in `block in index'
  lib/gitlab/gitaly_client.rb:193:in `allow_n_plus_1_calls'
  app/controllers/root_controller.rb:17:in `index'
  lib/gitlab/i18n.rb:47:in `with_locale'
  lib/gitlab/i18n.rb:53:in `with_user_locale'
  app/controllers/application_controller.rb:337:in `set_locale'
  lib/gitlab/middleware/multipart.rb:93:in `call'
  lib/gitlab/request_profiler/middleware.rb:14:in `call'
  lib/gitlab/middleware/go.rb:17:in `call'
  lib/gitlab/etag_caching/middleware.rb:11:in `call'
  lib/gitlab/middleware/read_only.rb:30:in `call'
  lib/gitlab/request_context.rb:18:in `call'
  lib/gitlab/metrics/requests_rack_middleware.rb:27:in `call'

My config/database.yml and mysql selects:

production:
  adapter: mysql2
  database: "gitlab"
  username: gitlab
  password: "gitlab"
  host: localhost
  encoding: utf8

mysql> SHOW VARIABLES WHERE Variable_name LIKE 'character\_set\_%' OR Variable_name LIKE 'collation%';
+--------------------------+-----------------+
| Variable_name            | Value           |
+--------------------------+-----------------+
| character_set_client     | utf8            |
| character_set_connection | utf8            |
| character_set_database   | utf8            |
| character_set_filesystem | binary          |
| character_set_results    | utf8            |
| character_set_server     | utf8            |
| character_set_system     | utf8            |
| collation_connection     | utf8_general_ci |
| collation_database       | utf8_general_ci |
| collation_server         | utf8_general_ci |
+--------------------------+-----------------+
10 rows in set (0.01 sec)

mysql> SELECT @@character_set_database, @@collation_database;
+--------------------------+----------------------+
| @@character_set_database | @@collation_database |
+--------------------------+----------------------+
| utf8                     | utf8_general_ci      |
+--------------------------+----------------------+
1 row in set (0.00 sec)

mysql> use gitlab;
mysql> show variables like "character_set_database";
+------------------------+-------+
| Variable_name          | Value |
+------------------------+-------+
| character_set_database | utf8  |
+------------------------+-------+


mysql> show table status like 'push_event_payloads';
+---------------------+--------+---------+------------+-------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
| Name                | Engine | Version | Row_format | Rows  | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation       | Checksum | Create_options | Comment |
+---------------------+--------+---------+------------+-------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
| push_event_payloads | InnoDB |      10 | Dynamic    | 14067 |            187 |     2637824 |               0 |            0 |   4194304 |           NULL | 2017-10-23 14:04:42 | 2017-10-23 14:22:53 | NULL       | utf8_unicode_ci |     NULL |                |         |
+---------------------+--------+---------+------------+-------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
1 row in set (0.00 sec)

The database was created by:

CREATE DATABASE IF NOT EXISTS `gitlab` DEFAULT CHARACTER SET `utf8` COLLATE `utf8_general_ci`;

Following this guide (https://docs.gitlab.com/ce/install/database_mysql.html#tables-and-data-conversion-to-utf8mb4) I get same error.