Fix pipeline when USE_LATEST_CAPI=true is used (#3714)

- Remove stemcell field from CAPI release in use-latest-capi.yml ops file
- Remove unused jumpbox private key extraction in create-bosh-lite workflow

These changes resolve deployment issues when using the latest CAPI release
by ensuring the ops file properly removes conflicting release metadata.

Author: anujc25

.github/ops-files/use-latest-capi.yml

@@ -8,3 +8,6 @@
 
 - type: remove
   path: /releases/name=capi/sha1?
+
+- type: remove
+  path: /releases/name=capi/stemcell?

.github/workflows/create-bosh-lite.yml

@@ -124,8 +124,6 @@ jobs:
           cd $env_name/bbl-state
           eval "$(bbl print-env --shell-type posix)"
           
-          jq -r .bosh.jumpbox_private_key metadata.json > /tmp/${env_name}.priv
-
           bosh upload-release "https://bosh.io/d/github.com/cloudfoundry/capi-release?v=$capi_release_version"          
       - name: Deploy cf
         run: |