Adding conditions for legal basis fields

[galvana]

Description Of Changes

Adding This legal basis is flexible field field above Legal basis for processing. The flexible field is only visible for GVL systems and is used as an indicator for why the Legal basis for processing field is enabled or disabled. The Legal basis for processing field will always be editable for systems not associated with a vendor.

Code Changes

• [ ] Updated PrivacyDeclarationForm.tsx with the This legal basis is flexible field field
• [ ] Added Cypress tests

Steps to Confirm

• [ ] Startup fidesplus with Compass enabled
• [ ] Create a system from the 1plusX vendor
• [ ] Navigate to data uses
• [ ] Click on Analytics for Advertising Performance
• [ ] The This legal basis is flexible field should be set to true and be disabled
• [ ] The legal basis field underneath should be editable
• [ ] Go back to the data use list and click on Profiling for personalization
• [ ] The This legal basis is flexible field should be set to false and be disabled
• [ ] The legal basis field underneath should not be editable
• [ ] Create new system but don't associate it to a Vendor
• [ ] Navigate to data uses
• [ ] Click on Add data use
• [ ] The This legal basis is flexible field should not be present and the legal basis field should be editable

Pre-Merge Checklist

• [ ] All CI Pipelines Succeeded
• Documentation:
  • [ ] documentation complete, PR opened in fidesdocs
  • [ ] documentation issue created in fidesdocs
• [ ] Issue Requirements are Met
• [ ] Relevant Follow-Up Issues Created
• [ ] Update CHANGELOG.md
• [ ] For API changes, the Postman collection has been updated