Add lalitb and ThomsonTan as approvers

[reyang]

Discussed during the Oct. 7th, 2020 SIG meeting.

@lalitb has been actively contributing to OpenTelemetry C++ across many modules as well as general improvements to the CI and infrastructure. He is also actively driving the better design of OpenTelemetry C++ API/SDK.

PRs @lalitb has authored:

• cmake build with gcc4.8 #354
• fix compile time warnings #352
• Support adding links to span #351
• Http Client API #309
• fix context data structure to support multiple attributes #330

PRs @lalitb has contributed:

• Add functionality to explicitely specify a span parent #349
• Adding a second Dockerfile supporting C++20 for cmake C++20 tests #211
• Remove static global context_handler_ variable #322
• Correct type of size_t - size_t to be size_t in tracez_processor_test #353
• Add spellcheck #54
• Set ids for spans #290
• Add missing include folders for example OTLP exporter #301
• Visual Studio compiler warnings clean-up #315

@ThomsonTan has been activity contributing to the overall OpenTelemetry project, including the specs, .NET client and C++ client.

PRs @ThomsonTan has authored in OpenTelemetry C++:

• Add missing include folders for example OTLP exporter #300
• Add missing include folders for example OTLP exporter #301
• Update sample decision name based on spec update #327
• Remove unnecessary reference to StartSpanOptions #338
• AddEvent support for Span #343
• Change type of Resize capacity from int to size_t #346
• Add explicit type conversion to narrower data type #347
• Correct type of size_t - size_t to be size_t in tracez_processor_test #353

@ThomsonTan has also contributed to several PRs in multiple OpenTelemetry repositories, there are too many to list out here.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@7826040). Click here to learn what that means.
The diff coverage is n/a.

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