Fix a regression in plugin install command

[mostafa]

Ticket(s)

N/A

Description

I found that the gateway plugin install command to properly install plugins, and fails in the middle. This is a regression I introduced in #310, which I fixed in this PR.

Related PRs

• Add support for installing plugins from locally downloaded archive files #310

Development Checklist

• I have added a descriptive title to this PR.
• I have squashed related commits together.
• I have rebased my branch on top of the latest main branch.
• I have performed a self-review of my own code.
• I have commented on my code, particularly in hard-to-understand areas.
• I have added docstring(s) and type annotations to my code.
• I have made corresponding changes to the documentation (docs).
• I have added tests for my changes.

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