[build] inline dev-build upload in deploy.sh

[pq]

Removes the call to plugin..dart deploy in favor of a bash implementation inline.

Fixes: #8866 .

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[gemini-code-assist]

Code Review

This pull request updates the tool/kokoro/deploy.sh script to directly upload the plugin zip file to the JetBrains Marketplace using curl, replacing the previous ./bin/plugin deploy command. The script now includes logic to retrieve an authentication token and verify the existence of the zip file before upload. A review comment highlighted that the new curl command lacks proper error handling and has a robustness issue due to an unquoted variable, recommending the use of the --fail flag and quoting the $ZIP_FILE variable.

[helin24]

😆 ... wow that is a small script