**Apache Airflow version**: 1.10.12

**Kubernetes version** : 1.17.9

**Environment**:

- **Cloud provider or hardware configuration**: Azure Kubernetes Service
- **OS** (e.g. from /etc/os-release): Linux
- **Install tools**: Helm chart (/chart in repo) 
- **Others**:

**What happened**:
Pod cannot run since `airflow-cleanup-pods` is not in $PATH
```
Error: failed to start container "airflow-cleanup-pods": Error response from daemon: OCI runtime create failed: container_linux.go:349: starting container process caused "exec: \"airflow-cleanup-pods\": executable file not found in $PATH": unknown
```

**What you expected to happen**: 
Cleanup job pod runs

<!-- What do you think went wrong? -->

**How to reproduce it**:
* Deploy Helm Chart
* Manually trigger `airflow-cleanup ` CronJob 
* See it cannot run since `airflow-cleanup-pods` is not in $PATH
airflow/cli/cli_parser.py
ARG_FLOWER_URL_PREFIX = Arg(
    ("-u", "--url-prefix"),
    default=conf.get('celery', 'FLOWER_URL_PREFIX'),
    help="URL prefix for Flower")
ARG_FLOWER_BASIC_AUTH = Arg(
    ("-A", "--basic-auth"),
    default=conf.get('celery', 'FLOWER_BASIC_AUTH'),
    help=("Securing Flower with Basic Authentication. "
          "Accepts user:password pairs separated by a comma. "
          "Example: flower_basic_auth = user1:password1,user2:password2"))
ARG_TASK_PARAMS = Arg(
    ("-t", "--task-params"),
    help="Sends a JSON params dict to the task")
ARG_POST_MORTEM = Arg(
    ("-m", "--post-mortem"),
    action="store_true",
    help="Open debugger on uncaught exception")
ARG_ENV_VARS = Arg(
    ("--env-vars", ),
    help="Set env var in both parsing time and runtime for each of entry supplied in a JSON dict",
    type=json.loads)
ARG_CONN_ID = Arg(
    ('conn_id',),
    help='Connection id, required to get/add/delete a connection',
    type=str)
ARG_CONN_ID_FILTER = Arg(
    ('--conn-id',),
    help='If passed, only items with the specified connection ID will be displayed',
    type=str)
ARG_CONN_URI = Arg(