working-groups/buildpacks: Add private repos, remove one

- Add 2 buildpacks team private repos
- Remove `buildpackapplifecycle` which should be part of Diego/Platform group

Author: arjun024

toc/working-groups/app-runtime-interfaces.md

@@ -113,7 +113,8 @@ areas:
   - cloudfoundry/brats
   - cloudfoundry/binary-builder
   - cloudfoundry/buildpack-packager
-  - cloudfoundry/buildpackapplifecycle
+  - cloudfoundry/buildpacks-envs
+  - cloudfoundry/buildpacks-workstation
   - cloudfoundry/buildpacks-ci
   - cloudfoundry/buildpacks-feature-eng-ci
   - cloudfoundry/buildpacks-github-config