Protected containers: New GraphQL field "protectionRuleExists"

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What does this MR do and why?

• This MR is preparation (pre-work) for a feature similar to the Protected badge in the context of "Protected packages":
  • #467718 (closed) => !156539 (merged)
  • #441346 -> !158600 (merged)
• When working on a similar feature in the context of "Protected packages", it was necessary to add a new GraphQL field "protectionRuleExists" to determine if a protection rule exists for a given package, see !146206 (merged) and !141134 (merged)
• This MR focusses on adding this a new GraphQL field "protectionRuleExists" to the container repository type that can be consumed in upcoming MRs

🛠 with ❤ at Siemens

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

MR Checklist (@gerardo-navarro)

• Changelog entry added, if necessary
• Documentation created/updated via this MR
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Tested in all supported browsers
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the javascript style guides
• Conforms to the database guides

DB Query

WITH "container_names_and_types_cte" AS MATERIALIZED (
  SELECT *
  FROM unnest(ARRAY['flightjs/flight/5','flightjs/flight/4','flightjs/flight/3','flightjs/flight/2','flightjs/flight']) AS x(repository_path)
)
SELECT
  container_names_and_types_cte."repository_path",
  EXISTS(
    SELECT 1
    FROM "container_registry_protection_rules"
    WHERE "container_registry_protection_rules"."project_id" = 7 AND
      (container_names_and_types_cte."repository_path" ILIKE REPLACE(REPLACE(REPLACE(repository_path_pattern, '%', '\%'), '_', '\_'), '*', '%'))
  ) AS protected
FROM container_names_and_types_cte

Screenshots or screen recordings

How to set up and validate locally

1. Execute the following GraphQL query

curl --request POST \
  --url http://gdk.test:3000/api/graphql \
  --header 'Authorization: Bearer ypCa3Dzb23o5nvsixwPA' \
  --header 'Content-Type: application/json' \
  --data '{"query":"query {\n\tproject(fullPath: \"flightjs/Flight\") {\n\t\tcontainerRepositories{\n\t\t\tnodes {\n\t\t\t\tid\n\t\t\t\tpath\n\t\t\t\tname\n\t\t\t\tprotectionRuleExists\n\t\t\t}\n\t\t}\n\t}\n}\n"}'

2. Look at the console output; you should just see one SQL query related to the new field "protectionRuleExists".

Related to #441346