chore(litserve): added RAG deployment example in readme (#231)

* chore(litserve): added RAG deployment example in readme

* fixed indentation

* Update README.md

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Co-authored-by: Akshay Pachaar <[email protected]>
Co-authored-by: William Falcon <[email protected]>

Author: 3 people

README.md

@@ -144,6 +144,7 @@ Use LitServe to deploy any model or AI service: (Gen AI, classical ML, embedding
 <strong>Featured examples</strong><br>
 <strong>Toy model:</strong>      <a target="_blank" href="#define-a-server">Hello world</a>
 <strong>LLMs:</strong>           <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-a-private-llama-3-8b-api">Llama 3 (8B)</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/openai-fault-tolerant-proxy-server">LLM Proxy server</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-ai-agent-with-tool-use">Agent with tool use</a>
+<strong>RAG:</strong>            <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-a-private-llama-3-1-rag-api">RAG API</a>
 <strong>NLP:</strong>            <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-any-hugging-face-model-instantly">Hugging face</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-a-hugging-face-bert-model">BERT</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-text-embedding-api-with-litserve">Text embedding API</a>
 <strong>Multimodal:</strong>     <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-open-ai-clip-with-litserve">OpenAI Clip</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-a-multi-modal-llm-with-minicpm">MiniCPM</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-phi3-5-vision-api-with-litserve">Phi-3.5 Vision Instruct</a>
 <strong>Audio:</strong>          <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-open-ai-s-whisper-model">Whisper</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-an-music-generation-api-with-meta-s-audio-craft">AudioCraft</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-an-audio-generation-api">StableAudio</a>, <a target="_blank" href="https://lightning.ai/lightning-ai/studios/deploy-a-noise-cancellation-api-with-deepfilternet">Noise cancellation (DeepFilterNet)</a>