[FEATURE] Migrate away from Utf8Json to System.Text.Json for serialization

[Scrambles56]

Is your feature request related to a problem?

We currently use a copied and internalized version of Utf8Json, which the upstream is no longer maintained. This not only may leave us open potential unpatched security issues or bugs within Utf8Json, it has also caused or contributed to a handful of other issues #424, #370, #318.

What solution would you like?

Migrate the client's JSON serialization implementation to instead use System.Text.Json.

What alternatives have you considered?

Leaving the Utf8Json implementation as is.

Do you have any additional context?

elasticsearch-net migrated to System.Text.Json in v8

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The scope of this issue was expanded by @Xtansia, see below for original issue.

Original Issue Text

Is your feature request related to a problem?

As a developer, I'm trying to reduce the amount of dependencies I'm taking on in my projects, and choose to use Microsofts default JSON serializer, System.Text.Json.

What solution would you like?

An implementation of the IOpenSearchSerializer that uses System.Text.Json, that provides equivalent behaviour to the existing Newtonsoft implementation.

What alternatives have you considered?

At the moment, the fallback is very isolated usage of the Newtonsoft package.

Do you have any additional context?

N/A

[Xtansia]

I've expanded the scope of this issue to instead be migrating away from Utf8Json to System.Text.Json as the primary serialization library of the clients.

[Djcarrillo6]

Hi @Xtansia, I'd like to request assignment on this issue.

[Xtansia]

@Djcarrillo6 You're more than welcome to have a go at this issue

[goldenc]

any update on this? we would like to move away from Newtonsoft.Json but its a bit tricky without a proper System.Text.Json open search implementation

[Xtansia]

any update on this? we would like to move away from Newtonsoft.Json but its a bit tricky without a proper System.Text.Json open search implementation

@goldenc There's been no updates yet to the best of my knowledge, I'm unsure if @Djcarrillo6 made any progress. So would be great if anyone was willing to make contributions towards this goal.

[Djcarrillo6]

Yeah @Xtansia I've been running into road block after road block. If anyone else would like to also work on this, please feel free.