Facing timeout issues on migration step

Recently we added timeouts for our database with configuration like
Configuration from `database.yml`
connect_timeout: 5
read_timeout: 5
write_timeout: 5
checkout_timeout: 5
All values are in seconds

---

### Steps to reproduce
When i run `cap production deploy` the deployment fails on migration step and gives error
Mysql2::Error::TimeoutError: Timeout waiting for a response from the last query.

### Expected behavior
We want use `MAX_EXECUTION_TIME=90000 rake db:migrate` during our cap deploy and we will add a variable `max_execution_time` in our `database.yml` which will default to 5 seconds.
Additionally we could inject `read_timeout` also along with it if the max execution time doesn't work alone.

### Actual behavior
We cannot control the injection of this variable because our Capfile uses `capistrano/rails` which will run `rake db:migrate` without maximum execution time and our migration could take much more time than our DB timeouts.

Start with the Capfile and the capistrano/rails task that runs rake db:migrate, then review the database.yml timeout settings described in the issue. Check how MAX_EXECUTION_TIME=90000 and the proposed max_execution_time setting would relate to the migration command and MySQL timeouts. Done means the deployment migration can use the requested execution-time or timeout configuration without the reported failure.

Written by the indexing model from the issue text.