Tooling: Set verify-deps-before-run to install instead of warn

[tbradsha]

Since upgrading to pnpm 10 (#41821) and setting verify-deps-before-run to warn, we often get warnings about things being outdated:

 WARN  Your node_modules are out of sync with your lockfile. The workspace structure has changed since last install

This PR switches the value to install.

Proposed changes:

Some other options considered:

• keep value as warn: this prints to STDOUT instead of STDERR, so pollutes command substitution
• value to false: this prevents things from being updated
• value to prompt: might break things in non-interactive contexts, and doesn't solve the issue if someone chooses "No"

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
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Jetpack product discussion

Does this pull request change what data or activity we track or use?

Testing instructions:

• Go to '..'

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