Protected packages/containers: Set alpha for GraphQL rules elements

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What does this MR do and why?

• Related to #416381 (closed)
• Forgot to set the alpha marking in previous MR, see !127022 (merged)
• Addressing comment from @10io, see #416381 (comment 1944240887)

🛠 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

Screenshots or screen recordings

Before	After

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Go to http://gdk.test:3000/-/graphql-explorer
2. You can use the following graphql query

query {
	project(fullPath: "flightjs/Flight") {
		packagesProtectionRules(first: 10) {
			nodes {
				id
				packageNamePattern
				packageType
				minimumAccessLevelForPush
			}
    }
	}
}