[ENH] Implemented `NB_FEDERATE_REMOTE_PUBLIC_NODES` env var

[rmanaem]

• Closes #62

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• [x] Tests pass
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• [ ] Tests have been added

For bug fixes:

• [ ] There is at least one test that would fail under the original bug conditions.

[coveralls]

Pull Request Test Coverage Report for Build 9274359452

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 28 of 29 (96.55%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.08%) to 96.914%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tests/test_utility.py	12	13	92.31%
<!--	Total:	28	29	96.55%	-->

Totals
Change from base Build 9224646794:	-0.08%
Covered Lines:	471
Relevant Lines:	486

---

💛 - Coveralls

[rmanaem]

provide basic docs for this new feature. if README isn't the place, then please make a PR against the ENV var table in the main docs and link here

Addressing that here https://github.com/neurobagel/recipes/issues/60

add a basic integration test to make sure the ENV var does what we think it does

Test has been added

[surchs]

:rocket: PR was released in v0.2.0 :rocket: