Skip streaming test if offline

[rly]

Motivation

Tests should pass when I'm on a plane without internet.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.21%. Comparing base (a08b34a) to head (b2d5ec8).
⚠️ Report is 15 commits behind head on dev.

Additional details and impacted files

@@           Coverage Diff           @@
##              dev    #2113   +/-   ##
=======================================
  Coverage   95.21%   95.21%           
=======================================
  Files          28       28           
  Lines        2840     2840           
  Branches      729      729           
=======================================
  Hits         2704     2704           
  Misses         80       80           
  Partials       56       56           

Flag	Coverage Δ
integration	74.33% <ø> (ø)
unit	85.07% <ø> (ø)

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[stephprince]

Could also test the URL to be more specific for connectivity issues like in the ROS3 tests, but I think either works!

pynwb/tests/integration/ros3/test_ros3.py

Lines 23 to 26 in f56b6f4

	try:
	urllib.request.urlopen('https://dandiarchive.s3.amazonaws.com/ros3test.nwb', timeout=1)
	except urllib.request.URLError:
	self.skipTest("Internet access to DANDI failed. Skipping all Ros3 streaming tests.")

[rly]

Ah, I didn't realize that urllib.request.urlopen simply opens the connection but does not download the file. Will update