[BE] Extend GraphQL for frontend for CSP

Why are we doing this work

In order for frontend to annotate the group as CSP and the policies as "instance-level policies", we should surface this information from the backend.

We should also ensure that policy scope can be configured for all instance projects and groups.

Relevant links

• FE issue
• PoC

Non-functional requirements

• Documentation:
• Feature flag:
• Performance:
• Testing:

Implementation plan

• Extend ee/app/graphql/ee/types/namespace_type.rb to indicate if a group is a CSP
• Extend merge_project_relationship in ee/app/finders/security/security_policy_base_finder.rb and expose config.source.csp
• Test and update the code paths to allow proper policy scope configuration by considering all projects / groups in the instance

Verification steps

1. Query csp attribute for a namespace and verify that it returns true for a CSP group and false for other groups

    {
     namespace(fullPath: "<group-path>") {
       id
       approvalPolicies(relationship: INHERITED) {
         nodes {
           name
           enabled
           csp
         }
       }
       scanExecutionPolicies(relationship: INHERITED) {
         nodes {
           name
           enabled
           csp
         }
       }
       vulnerabilityManagementPolicies(relationship: INHERITED) {
         nodes { 
           name
           enabled
           csp
         }
       }
       pipelineExecutionPolicies(relationship: INHERITED) {
         nodes { 
           name
           enabled
           csp
         }
       }
       pipelineExecutionSchedulePolicies(relationship: INHERITED) {
         nodes { 
           name
           enabled
           csp
         }
       }
     }
   }

2. Try to assign various groups and projects in the policy scope of the CSP configuration and verify that they are returned in the dropdown results