fix: bring back dell template (#2880)

This template is definitely needed since it (and related docker, which
will push soon) is used by folks at Dell.

llama_stack/templates/dell/build.yaml

@@ -0,0 +1,35 @@
+version: 2
+distribution_spec:
+  description: Dell's distribution of Llama Stack. TGI inference via Dell's custom
+    container
+  providers:
+    inference:
+    - remote::tgi
+    - inline::sentence-transformers
+    vector_io:
+    - inline::faiss
+    - remote::chromadb
+    - remote::pgvector
+    safety:
+    - inline::llama-guard
+    agents:
+    - inline::meta-reference
+    telemetry:
+    - inline::meta-reference
+    eval:
+    - inline::meta-reference
+    datasetio:
+    - remote::huggingface
+    - inline::localfs
+    scoring:
+    - inline::basic
+    - inline::llm-as-judge
+    - inline::braintrust
+    tool_runtime:
+    - remote::brave-search
+    - remote::tavily-search
+    - inline::rag-runtime
+image_type: conda
+additional_pip_packages:
+- aiosqlite
+- sqlalchemy[asyncio]