refactor: use watchDebounced from @netlify/dev-utils

[keanu-a]

Summary

Fixes #EX-324

Replaced all usages from cli watchDebounced with function from @netlify/dev-utils package. Removed function from command-helpers.ts and unused imports.

Ref: https://github.com/netlify/primitives/blob/main/packages/dev-utils/src/lib/watch-debounced.ts

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[github-actions]

📊 Benchmark results

Comparing with aef99f7

• Dependency count: 1,080 (no change)
• Package size: 290 MB ⬇️ 0.00% decrease vs. aef99f7
• Number of ts-expect-error directives: 385 ⬇️ 0.78% decrease vs. aef99f7

[serhalp]

LGTM, just one follow-up

[serhalp]

this time I don't think github is fooling me 😁 — we can remove this dependency!

[keanu-a]

This time github isn't fooling you! But we do use other submodules from the lodash package 😅
Ex: https://github.com/netlify/cli/blob/main/src/commands/base-command.ts

import merge from 'lodash/merge.js'
import pick from 'lodash/pick.js'

[eduardoboucas]

LGTM