Remove --config option from test and build commands

[coderabbitai]

Description

The --config option in both the test and build commands should be removed. This option allows overriding the build config file path, but this functionality is unnecessary. Similar to how npm run doesn't allow overriding package.json, our CLI should use the default config file location only.

Context

This was discussed in PR #71:

• PR: Test command #71
• Comment: Test command #71 (comment)

Affected Commands

• jammin test --config <path>
• jammin build --config <path>

Requested by: @tomusdrw