[PLAT-11750] Handle edge case when capturing a URL request with a null URL before Bugsnag is initialized

[kstenerud]

Goal

Any spans created before Bugsnag is initialized get stored in an "early spans" list. There is an edge case where a URL request with a nil URL causes the span code to return a nil span, which crashes when we try to add the resulting nil pointer to the "early spans" list.

Changeset

Add a nil guard around the span code.

Testing

Added repro case as an e2e test.

[github-actions]

BugsnagPerformance.framework binary size did not change - 510,264 bytes

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  -0.0%      -4  -0.0%      -4    [__TEXT]
  [ = ]       0  [ = ]       0    TOTAL

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