Ensure traditional jetpack docker up works

Author: kraftbj

tools/docker/docker-compose.yml

@@ -52,13 +52,13 @@ services:
 
   monorepo:
     build:
-      context: ${HOST_CWD}/tools/docker
+      context: ${HOST_CWD:-.}/tools/docker
       dockerfile: Dockerfile.monorepo
       args:
         PHP_VERSION: ${PHP_VERSION}
         COMPOSER_VERSION: ${COMPOSER_VERSION}
         NODE_VERSION: ${NODE_VERSION}
         PNPM_VERSION: ${PNPM_VERSION}
     volumes:
-      - ${HOST_CWD}:/usr/local/src/jetpack-monorepo
+      - ${HOST_CWD:-.}:/usr/local/src/jetpack-monorepo
     working_dir: /usr/local/src/jetpack-monorepo