Add remediation support for drush yaml checks

[yusufhm]

Another big PR, which introduces a number of changes:

• Breach is now an interface, with a generator for the common functions.

  • This allows for better handling remediations and the result for a check in general.
  • It also opens up future possibilities of having custom Breach types per Check and so on.

• Added a Remediation struct and included it in the Result struct.

• Updated the Remediate() signature in the Check interface to be more generic and without a return value.

  • It now expects the Check's Remediate implementation to loop through all the breaches and update the Remediation inside each one.

• Updated the logic in ProcessCheck to call Remediate() for each Check after RunCheck() has been called.

  • Also added a DetermineResultStatus() to Result so we can have better logic outside of RunCheck() which determines the result based on the Breaches detected and Remediations performed.
    • This allows for a Check to focus on just analysing the data and reporting Breaches.
    • It also means that almost all tests had to be updated to reflect that change, since the Result.Status is not being manually set in different places now.

• Finally, added two new attributes to the drush-yaml check, remediate-command & remediate-msg, along with the corresponding Remediate() logic. This allows us to define a check like below:

  checks:
    drush-yaml:
      - name: '[DATABASE] Ensure clamav is enabled'
        severity: high
        command: 'config:get clamav.settings'
        config-name: clamav.settings
        values:
          - key: enabled
            value: true
            truthy: true
        remediate-command: |
          #!/bin/bash
          set -eu
          drush config:set clamav.settings enabled true
        remediate-msg: ClamAV config was remediated by enabling it

  Shipshape will use the command specified to fix the issue and on success output the message specified:

  # Remediations
  
    ### [DATABASE] Ensure clamav is enabled
      -- ClamAV config was remediated by enabling it