fix: unsetenv not existing on Windows

[JoanFM]

Goals:

• ...
• ...
• check and update documentation. See guide and ask the team.

[codecov]

Codecov Report

Merging #4800 (cfd7ef7) into master (a32bfe2) will decrease coverage by 0.05%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #4800      +/-   ##
==========================================
- Coverage   88.01%   87.96%   -0.06%     
==========================================
  Files         119      119              
  Lines        9012     9013       +1     
==========================================
- Hits         7932     7928       -4     
- Misses       1080     1085       +5     

Flag	Coverage Δ
jina	87.96% <100.00%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
jina/__init__.py	65.88% <100.00%> (ø)
jina/helper.py	81.75% <100.00%> (+0.02%)	⬆️
...a/orchestrate/deployments/config/docker_compose.py	99.00% <0.00%> (-1.00%)	⬇️
jina/orchestrate/flow/base.py	89.45% <0.00%> (-0.59%)	⬇️
jina/serve/runtimes/gateway/http/__init__.py	100.00% <0.00%> (+2.22%)	⬆️

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[github-actions]

Latency summary

Current PR yields:

• 😶 index QPS at 1324, delta to last 2 avg.: +0%
• 😶 query QPS at 76, delta to last 2 avg.: +0%
• 🐎🐎 avg flow time within 1.7995 seconds, delta to last 2 avg.: +10%
• 🐎🐎 import jina within 0.4816 seconds, delta to last 2 avg.: +6%

Breakdown

Version	Index QPS	Query QPS	Avg Flow Time (s)	Import Time (s)
current	1324	76	1.7995	0.4816
3.4.3	1347	79	1.4542	0.4475
3.4.2	1312	72	1.8056	0.46

Backed by latency-tracking. Further commits will update this comment.