Switching to SpanConcurrentHashMap in HttpUrlConnection instr

[eyalkoren]

Implementing #2092 for HttpUrlConnection instrumentation

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• Start Time: 2021-12-02T08:39:17.097+0000

• Duration: 72 min 8 sec

• Commit: 5ee4f91

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Test	Results
Failed	0
Passed	2557
Skipped	21
Total	2578

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