Generalize encoding/decoding tests

[thake]

The current unit tests for encoding have been refactored as part of #160. Duplicate tests have been removed, and some bugs have been fixed on the way.

[Chuckame]

Hello back, happy new year. Happy to come back on the project, I didn't have that much time until now! Feel free to tell me if you want me pushing a commit on this branch if you don't have time or di not understand :)

[Chuckame]

Here is what I'm talking about: taking the expected avro representation, encoding it with avro lib, and then use it to test our decoding part

Suggested change

	inline fun <reified T> EnDecoder.testEncodeDecode(
	value: T,
	shouldMatch: RecordBuilderForTest,
	serializer: KSerializer<T> = avro.serializersModule.serializer<T>(),
	schema: Schema = avro.schema(serializer)
	) {
	val encoded = testEncodeIsEqual(value, shouldMatch, serializer, schema)
	testDecodeIsEqual(encoded, value,serializer, schema)
	}
	inline fun <reified T> EnDecoder.testEncodeDecode(
	value: T,
	shouldMatch: RecordBuilderForTest,
	serializer: KSerializer<T> = avro.serializersModule.serializer<T>(),
	schema: Schema = avro.schema(serializer)
	) {
	testEncodeIsEqual(value, shouldMatch, serializer, schema)
	testDecodeIsEqual(avroLibBinaryEncoding(shouldMatch.toAvro(schema)), value, serializer, schema)
	}

[Chuckame]

Let's merge it as it is, as I'm currently adding ktlint, spotless and reformat everything, and also moving forward on the v2, so having simpler tests will be awesome.

I'm not a fan of the open door of multiple EnDecode implementation as it complexifies for a need that we don't have now, and mostly avro4k should not have multiple way of doing avro or users won't really know what to chose.

If we want to test decoding and encoding in multiple container types (single object, confluent schema registry, ...), let's tackle some "wrapping" api to be able of decorate a binary avro message with whatever we need.

I'll do a little other PR to fix this point after all the code reformat