chore: Improve Vercel/Neon syncEnvVars build extensions docs #3853

Job	Run time
typecheck / typecheck	6m 9s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	1m 50s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	1m 48s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	4m 48s
e2e / 🧪 CLI v3 tests (windows-latest - npm)	3m 30s
units / internal / 🧪 Unit Tests: Internal (1, 8)	5m 15s
units / internal / 🧪 Unit Tests: Internal (2, 8)	4m 53s
units / internal / 🧪 Unit Tests: Internal (3, 8)	5m 2s
units / internal / 🧪 Unit Tests: Internal (4, 8)	4m 41s
units / internal / 🧪 Unit Tests: Internal (5, 8)	4m 11s
units / internal / 🧪 Unit Tests: Internal (6, 8)	3m 19s
units / webapp / 🧪 Unit Tests: Webapp (6, 8)	5m 44s
units / packages / 🧪 Unit Tests: Packages (1, 1)	5m 9s
units / webapp / 🧪 Unit Tests: Webapp (5, 8)	7m 10s
units / webapp / 🧪 Unit Tests: Webapp (8, 8)	2m 29s
units / internal / 🧪 Unit Tests: Internal (8, 8)	2m 3s
units / webapp / 🧪 Unit Tests: Webapp (2, 8)	4m 5s
units / webapp / 🧪 Unit Tests: Webapp (3, 8)	5m 22s
units / webapp / 🧪 Unit Tests: Webapp (4, 8)	3m 25s
units / webapp / 🧪 Unit Tests: Webapp (1, 8)	5m 43s
units / webapp / 🧪 Unit Tests: Webapp (7, 8)	2m 16s
units / internal / 🧪 Unit Tests: Internal (7, 8)	4m 10s
units / packages / 📊 Merge Reports	25s
units / internal / 📊 Merge Reports	26s
units / webapp / 📊 Merge Reports	42s
	1h 34m 35s

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