fix: integration tests

[anmonteiro]

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Summary

Fixes tests after #3948.

Explanation:

The tests added in #3948 re-define NETLIFY_AUTH_TOKEN which is used to decide whether the CLI should "expensively authenticate" or not. The fix is to stop reading the environmental variable just once at startup, to allow picking up re-definitions from tests.

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[github-actions]

📊 Benchmark results

Comparing with 9975b53

Package size: 377 MB

(no change)

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└───┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴──>
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Legend

• T-30 (9975b53): 377 MB
• T-29 (76b6206): 377 MB
• T-28 (1bf95f2): 377 MB
• T-27 (b830b8f): 377 MB
• T-26 (454e4d1): 377 MB
• T-25 (06f0d95): 377 MB
• T-24 (a1dc7a4): 368 MB
• T-23 (3ebfea9): 368 MB
• T-22 (127a1c6): 368 MB
• T-21 (12713ca): 368 MB
• T-20 (6424921): 368 MB
• T-19 (9902ec0): 368 MB
• T-18 (fb4fd7a): 368 MB
• T-17 (b557a4d): 368 MB
• T-16 (d7d1a83): 368 MB
• T-15 (5aada1e): 368 MB
• T-14 (db86f16): 363 MB
• T-13 (89ec45c): 363 MB
• T-12 (e6bde5b): 363 MB
• T-11 (8a59a03): 363 MB
• T-10 (501da79): 363 MB
• T-9 (c370149): 362 MB
• T-8 (0e0502c): 362 MB
• T-7 (effffec): 362 MB
• T-6 (0577c15): 363 MB
• T-5 (3dd9f74): 363 MB
• T-4 (c32fa07): 363 MB
• T-3 (32714f0): 362 MB
• T-2 (5b5b360): 363 MB
• T-1 (46374c4): 363 MB
• T (current commit): 377 MB

[erezrokah]

Closing in favor of #4186