Avoid processing undesired network tasks

[nachoBonafonte]

Avoid processing undesired network tasks activity when the task has not been processed properly by urlSessionTaskWillResume. We check if a taskId was registered or exit early.
Should fix remaining crashes in #447

[codecov]

Codecov Report

Patch coverage is 12.50% of modified lines.

❗ Current head 702421f differs from pull request most recent head ae373f9. Consider uploading reports for the commit ae373f9 to get more accurate results

Files Changed	Coverage
...ntation/URLSession/URLSessionInstrumentation.swift	12.50%

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