Fix vLLM endpoint to have correct suffix

docs/vllm.md

@@ -21,5 +21,5 @@ In your terminal where you're running MemGPT, run `memgpt configure` to set the
 
 If you have an existing agent that you want to move to the vLLM backend, add extra flags to `memgpt run`:
 ```sh
-memgpt run --agent your_agent --model-endpoint-type vLLM --model-endpoint http://localhost:8000
+memgpt run --agent your_agent --model-endpoint-type vllm --model-endpoint http://localhost:8000 --model ehartford/dolphin-2.2.1-mistral-7b
 ```

memgpt/local_llm/vllm/api.py

@@ -4,7 +4,7 @@
 
 from ..utils import load_grammar_file, count_tokens
 
-WEBUI_API_SUFFIX = "/completions"
+WEBUI_API_SUFFIX = "/v1/completions"
 DEBUG = False