add fuzz tests to multiple receivers and processors

[AdamKorcz]

Description

Adds fuzz tests for receiver handlers and processing of metrics, logs and traces. For receivers, the fuzz test will create an HTTP request with the fuzzers testcase as its body. For processors, the fuzzer will create random logs, metrics or traces and pass it to a routine that processes the data - for the most part either a processLogs/processMetrics/processTraces method or ConsumeLogs/ConsumeTraces which will then invoke the internal process routine.

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Fixes

Testing

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