Docs: Move tupload_texts() example from guides to reference

[agnieszka-m]

Proposed Changes?

SOLs suggested upload_bytes() is the method we should promote in the guides, since they can use it for all file types, not just text. I'm deleting upload_texts() examples from https://docs.cloud.deepset.ai/docs/upload-files-with-python#upload-texts-or-bytes and moving them to reference. The how-tos will just have examples of upload_bytes.

How did you test it?

Notes for the reviewer

I'm not sure the formatting is OK.

Screenshots (optional)

Checklist

• I have updated the referenced issue with new insights and changes
• If this is a code change, I have added unit tests
• I've used the conventional commit specification for my PR title
• I updated the docstrings
• If this is a code change, I added meaningful logs and prepared Datadog visualizations and alerts

[github-actions]

Coverage report

This PR does not seem to contain any modification to coverable code.

[FHardow]

Not sure if my suggestions will be a problem

[sjrl]

Hey @agnieszka-m there were a few indenting changes I made, that were hard to create as suggestions, so I just made a quick commit!