Adapt samples API to allow for filesystem less upload

[danielwinkler]

Feature Request

Is your feature request related to a problem? Please describe.

This is related to the PR and discussion from https://github.com/RageAgainstThePixel/ElevenLabs-DotNet/pull/25

If I want to add a sample to the voice, I have to write it to the filesystem first (see EditVoiceAsync). It would be great if we could pass in a ReadOnlyMemory<byte> like we get out the ClipData.

Some preliminary work was already in the above mentioned PR.

Cheers, daniel

[StephenHodgson]

Sounds good, open to PR.

Please make it an overload, don't replace existing method.

[RealStillkill]

Submitted pull request #40