Address ApplicationTests::FrameworksTest failure on Ubuntu 22.04

This commit address Rails Nightly failure at
https://buildkite.com/rails/rails-nightly/builds/191#018dc3d1-8fb2-4c35-ad1d-bd3891757361/1310-1318

This issue reproduces when the `default-mysql-client` apt package installs `mysql-client-8.0`
that raises `CR_CONN_HOST_ERROR` which is mapped to `ActiveRecord::DatabaseConnectionError`
while `mariadb-client` raises `CR_CONNECTION_ERROR` error which is mapped to `ActiveRecord::ConnectionNotEstablished`.

In this test, whichever exception `ActiveRecord::ConnectionNotEstablished` or `DatabaseConnectionError` is fine
as long as the connection is invalid.

- Steps to reproduce

Run this step at Linux box on Ubuntu Jammy or whatever `default-mysql-client` installs MySQL client, not MariaDB one.

```
git clone https://github.com/rails/rails
cd rails/railties
bundle install
bin/test test/application/initializers/frameworks_test.rb:285
```

- Failure fixed by this commit

```ruby
$ bin/test test/application/initializers/frameworks_test.rb:285
Run options: --seed 32832

F

Failure:
ApplicationTests::FrameworksTest#test_expire_schema_cache_dump_if_the_version_can't_be_checked_because_the_database_is_unhealthy [test/application/initializers/frameworks_test.rb:285]:
Expected /Failed to validate the schema cache because of ActiveRecord::ConnectionNotEstablished/ to match "Failed to validate the schema cache because of ActiveRecord::DatabaseConnectionError: There is an issue connecting with your hostname: 127.0.0.1.\n\nPlease check your database configuration and ensure there is a valid connection to your database.\n".

bin/test test/application/initializers/frameworks_test.rb:263

Finished in 6.299418s, 0.1587 runs/s, 0.6350 assertions/s.
1 runs, 4 assertions, 1 failures, 0 errors, 0 skips
```

- `default-mysql-client` package used by Rails CI

https://github.com/rails/buildkite-config/blob/3158d00b48da5a30f4319af1f7ac73f2b7094898/Dockerfile#L91

`default-mysql-client` installs different package per distribution, Ja
https://packages.ubuntu.com/jammy/default-mysql-client
https://packages.debian.org/bookworm/default-mysql-client

- Each error message are defined in these lines by these commits:
-- MariaDB
https://github.com/MariaDB/server/blob/eeba940311ed17d160023280783fd2bbb64abef3/sql-common/errmsg.c#L32
MariaDB/server@9075973

-- MySQL
https://github.com/mysql/mysql-server/blob/824e2b4064053f7daf17d7f3f84b7a3ed92e5fb4/libmysql/errmsg.cc#L39
mysql/mysql-server@964d5fd

Author: yahonda

railties/test/application/initializers/frameworks_test.rb

@@ -282,7 +282,7 @@ def show
             end
           end
 
-          assert_match(/Failed to validate the schema cache because of ActiveRecord::ConnectionNotEstablished/, error)
+          assert_match(/Failed to validate the schema cache because of ActiveRecord::(ConnectionNotEstablished|DatabaseConnectionError)/, error)
         end
       end
     end