Update mysql

Changes:

- https://github.com/docker-library/mysql/commit/bc6e37a: Merge pull request https://github.com/docker-library/mysql/pull/500 from Istador/escape_database_wildcard
- https://github.com/docker-library/mysql/commit/7a87af0: Escape database underscore wildcard
- https://github.com/docker-library/mysql/commit/a769034: Merge pull request https://github.com/docker-library/mysql/pull/667 from docker-library/github-actions
- https://github.com/docker-library/mysql/commit/ab66888: Add initial GitHub Actions CI

library/mysql

@@ -5,13 +5,13 @@ Maintainers: Tianon Gravi <[email protected]> (@tianon),
 GitRepo: https://github.com/docker-library/mysql.git
 
 Tags: 8.0.20, 8.0, 8, latest
-GitCommit: fef511444a9d2867c9e4e20f5b4062bc071c20a2
+GitCommit: bc6e37a2bed792b1c4fc6ab1ec3ce316e6a5f061
 Directory: 8.0
 
 Tags: 5.7.30, 5.7, 5
-GitCommit: 7397711170daed7ebba3bf373af143e5179906fc
+GitCommit: bc6e37a2bed792b1c4fc6ab1ec3ce316e6a5f061
 Directory: 5.7
 
 Tags: 5.6.48, 5.6
-GitCommit: d2ba5f1fd5c1f4002253b80575de9c759d22bb1e
+GitCommit: bc6e37a2bed792b1c4fc6ab1ec3ce316e6a5f061
 Directory: 5.6