Remove Functionality that Pulls Env Variables from Empty Keys

[cailyn-codes]

Addresses: #4731

Instead of pulling in environment values when a key is added in the env file with out the = we will now treat this case the same as if an = is present and set the value to an empty string.

[k8s-ci-robot]

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[KnVerey]

/approve
/hold for @natasha41575 to approve as well

[k8s-ci-robot]

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[natasha41575]

/lgtm
/hold cancel

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cailynse, KnVerey, natasha41575

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