fix: update k8s templates (#2645)

# What does this PR do?
- fix env variables
- use gpu for vllm
- add eks/apply.py for aws
- add template to set hf secret

## Test Plan
bash apply.sh

Co-authored-by: Eric Huang <erichuang@fb.com>

docs/source/distributions/k8s/stack-configmap.yaml

@@ -22,10 +22,10 @@ data:
       - provider_id: vllm-safety
         provider_type: remote::vllm
         config:
-          url: ${env.VLLM_SAFETY_URL:http://localhost:8000/v1}
-          max_tokens: ${env.VLLM_MAX_TOKENS:4096}
-          api_token: ${env.VLLM_API_TOKEN:fake}
-          tls_verify: ${env.VLLM_TLS_VERIFY:true}
+          url: ${env.VLLM_SAFETY_URL:=http://localhost:8000/v1}
+          max_tokens: ${env.VLLM_MAX_TOKENS:=4096}
+          api_token: ${env.VLLM_API_TOKEN:=fake}
+          tls_verify: ${env.VLLM_TLS_VERIFY:=true}
       - provider_id: sentence-transformers
         provider_type: inline::sentence-transformers
         config: {}
@@ -33,7 +33,7 @@ data:
       - provider_id: ${env.ENABLE_CHROMADB:+chromadb}
         provider_type: remote::chromadb
         config:
-          url: ${env.CHROMADB_URL:+}
+          url: ${env.CHROMADB_URL:=}
       safety:
       - provider_id: llama-guard
         provider_type: inline::llama-guard
@@ -48,7 +48,7 @@ data:
             host: ${env.POSTGRES_HOST:=localhost}
             port: ${env.POSTGRES_PORT:=5432}
             db: ${env.POSTGRES_DB:=llamastack}
-            user: ${env.POSTGRES_USER:llamastack}
+            user: ${env.POSTGRES_USER:=llamastack}
             password: ${env.POSTGRES_PASSWORD:=llamastack}
           responses_store:
             type: postgres
@@ -61,8 +61,8 @@ data:
       - provider_id: meta-reference
         provider_type: inline::meta-reference
         config:
-          service_name: ${env.OTEL_SERVICE_NAME:+}
-          sinks: ${env.TELEMETRY_SINKS:console}
+          service_name: "${env.OTEL_SERVICE_NAME:=\u200B}"
+          sinks: ${env.TELEMETRY_SINKS:=console}
       tool_runtime:
       - provider_id: brave-search
         provider_type: remote::brave-search