Added dependencies to k8s, LLM fixes

[ea-rus]

Description

Added handlers to cloud requirements:

• llama_index
• writer
• rag
  • added sentence-transformers for rag

Fixes llama handler error (presumably added by #8562):

• DFReader is default reader
• wrong usage of get_api_key
• fix openai deprecation error
• remove global api key binding

Fixes: #346
Fixes: #357
Fixes: #358
Fixes: https://github.com/mindsdb/mindsdb_private/issues/361

Type of change

(Please delete options that are not relevant)

• 🐛 Bug fix (non-breaking change which fixes an issue)

Verification Process

To ensure the changes are working as expected:

• Test Location: Specify the URL or path for testing.
• Verification Steps: Outline the steps or queries needed to validate the change. Include any data, configurations, or actions required to reproduce or see the new functionality.

Additional Media:

• I have attached a brief loom video or screenshots showcasing the new functionality or change.

Checklist:

• My code follows the style guidelines(PEP 8) of MindsDB.
• I have appropriately commented on my code, especially in complex areas.
• Necessary documentation updates are either made or tracked in issues.
• Relevant unit and integration tests are updated or added.

[paxcema]

FYI @martyna-mindsdb we will have to update this on #8245 if merged first.

[paxcema]

Looks good, I've made a note to update some bits in #8245 once this is merged.