…ultiples checks for packages definition (Kocal)

This PR was merged into the 2.x branch.

Discussion
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 Refactor "test_package.sh" to its original purpose, add multiples checks for packages definition

| Q              | A
| -------------- | ---
| Bug fix?       | no
| New feature?   | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations?  | no <!-- if yes, also update UPGRADE-*.md and src/**/CHANGELOG.md -->
| Documentation? | no <!-- required for new features, or documentation updates -->
| Issues         | Fix #... <!-- prefix each issue number with "Fix #", no need to create an issue if none exist, explain below instead -->
| License        | MIT

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Following the minor changes from #3086

Commits
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4949e62 Refactor "test_package.sh" to its original purpose, add multiples checks for packages definition