Add -y/--yes flag to force destructive commands without confirmation

[diego-feito-stori]

Description

To use in a batch process, I added the option to assume yes to destructive commands via a command line parameter because it is safer to have the default config safer.
To do this, I added the -y / --yes parameter.

Examples:

  pgcli --yes -c "ALTER TABLE foo DROP COLUMN bar;"
  pgcli -y -c "DROP TABLE test;"
  pgcli -c "ALTER TABLE foo DROP COLUMN bar;"

Test logs: behave.file.1.log - behave.file.2.log - pytest.file.1.log

Checklist

• I've added this contribution to the changelog.rst.
• I've added my name to the AUTHORS file (or it's already there).

• I installed pre-commit hooks (pip install pre-commit && pre-commit install).
• Please squash merge this pull request (uncheck if you'd like us to merge as multiple commits)

[j-bennet]

What's up with all the closed PRs?