Closes #3493 PHP warnings logged upon inserting a new Bootstrap grid

[bberndt-uaz]

Description

Fixes multiple php warnings in the log by adding the patch from this drupal.org issue for the CKEditor Bootstrap Grid module:

• Warning: Undefined array key "default_layout"

Related issues

3493

How to test

Probo review site: https://7b5e2985-cedf-4a13-ab91-3a35916c835d--pr-3494.probo.build

1. Edit any page containing a text area using the Standard text format
2. Click the "Bootstrap Grid" button in the editor toolbar
3. Click the Next button in the Select Columns modal
4. Save the grid or cancel out of it
5. Go to the Recent Log Messages at /admin/reports/dblog
6. Confirm that no Warning: Undefined array key "default_layout" PHP warnings are shown

Types of changes

Arizona Quickstart (install profile, custom modules, custom theme)

• Patch release changes
  • [x] Bug fix
  • [ ] Accessibility, performance, or security improvement
  • [ ] Critical institutional link or brand change
  • [ ] Adding experimental module
  • [ ] Update experimental module
• Minor release changes
  • [ ] New feature
  • [ ] Breaking or visual change to existing behavior
  • [ ] Upgrade experimental module to stable
  • [ ] Enable existing module by default or database update
  • [ ] Non-critical brand change
  • [ ] New internal API or API improvement with backwards compatibility
  • [ ] Risky or disruptive cleanup to comply with coding standards
  • [ ] High-risk or disruptive change (requires upgrade path, risks regression, etc.)
• Other or unknown
  • [ ] Other or unknown

Drupal core

• Patch release changes
  • [ ] Security update
  • [ ] Patch level release (non-security bug-fix release)
  • [ ] Patch removal that's no longer necessary
• Minor release changes
  • [ ] Major or minor level update
• Other or unknown
  • [ ] Other or unknown

Drupal contrib projects

• Patch release changes
  • [ ] Security update
  • [ ] Patch or minor level update
  • [ ] Add new module
  • [ ] Patch removal that's no longer necessary
• Minor release changes
  • [ ] Major level update
• Other or unknown
  • [ ] Other or unknown

Checklist

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.
• [ ] My change requires release notes.