pymongo integration

[hectorhdzg]

Add trace integration with pymongo

https://pypi.org/project/pymongo/

[hectorhdzg]

Would like to keep contributing to the project and we are missing multiple key integrations, let me know if there is any concern about this, if not will appreciate if you can assign this issue to me because I don't have permission for that

[c24t]

Fixed in #232, and opentelemetry-ext-pymongo was released with v0.3.0.