Implement self-metrics using opentelemetry for cgoreceiver

[dxsup]

Description

Implement metrics of kindling_telemetry_cgoreceiver_events_total and kindling_telemetry_cgoreceiver_channel_size using opentelemetry for cgoreceiver.

How Has This Been Tested?

Unit test.

=== RUN   TestCounterMutexMap
--- PASS: TestCounterMutexMap (1.07s)
=== RUN   TestCounterRwMutexMap
--- PASS: TestCounterRwMutexMap (1.39s)
=== RUN   TestCounterIntCombination
--- PASS: TestCounterIntCombination (0.23s)
=== RUN   TestCounterRwAtomicMap
--- PASS: TestCounterRwAtomicMap (0.36s)
PASS
ok      command-line-arguments  4.145s

Benchmark result. We are using RwAtomicMap.

goos: darwin
goarch: amd64
cpu: Intel(R) Core(TM) i5-6267U CPU @ 2.90GHz
BenchmarkCounterMutexMap
BenchmarkCounterMutexMap-4                   172           6849760 ns/op
BenchmarkCounterRwMutexMap
BenchmarkCounterRwMutexMap-4                 126           9374031 ns/op
BenchmarkCounterIntCombination
BenchmarkCounterIntCombination-4            1173           1119354 ns/op
BenchmarkCounterOtelCounter
BenchmarkCounterOtelCounter-4                 45          27502518 ns/op
BenchmarkCounterRwAtomicMap
BenchmarkCounterRwAtomicMap-4                772           1652800 ns/op
PASS
ok      command-line-arguments  7.634s

[NeJan2020]

LGTM