Preserve order of plugin invocation

[anaclaudiar]

This readme claims the order of plugin invocation is preserved, but that's not true given it iterates through Lua dictionary, where iteration is not predictable / ordered. If we use an index and ipairs, instead of pairs and no index, we can guarantee the order.

What this PR does / why we need it:

To execute lua plugins in order, as declared.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation only

How Has This Been Tested?

I have added a unit test to cover my change.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added tests to cover my changes.
• All new and existing tests passed.

[k8s-ci-robot]

@anaclaudiar: This issue is currently awaiting triage.

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[k8s-ci-robot]

Hi @anaclaudiar. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[ElvinEfendi]

/ok-to-test

[ElvinEfendi]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: anaclaudiar, ElvinEfendi

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