Prevent bootstrap of ZK from clearing previous dist binaries

[adsr]

Description

Presently protoc bootstrap gets wiped out by ZK bootstrap via this rm in install_dep. The fix in this patch is to invoke install_dep for ZK with subdir of dist/ instead of the top-level dist/, similar to the other deps.

Related Issue(s)

N/A

Checklist

• "Backport to:" labels have been added if this change should be back-ported
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

N/A

[vitess-bot]

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[deepthi]

@adsr I'm trusting that you have validated this locally. We'll get another approval for this.