Support trace-ignore in python agent

[alonelaval]

Please answer these questions before submitting your issue.

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• Question or discussion
• Bug
• Requirement
• Feature or performance improvement

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Question

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Bug

• Which version of SkyWalking, OS and JRE?

• Which company or project?

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  If possible, provide a way for reproducing the error. e.g. demo application, component version.

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Requirement or improvement

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[kezhenxu94]

Resolved by apache/skywalking-python#59