**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_STDERR = Arg(
    ("--stderr",),
    help="Redirect stderr to this file")
ARG_STDOUT = Arg(
    ("--stdout",),
    help="Redirect stdout to this file")
ARG_LOG_FILE = Arg(
    ("-l", "--log-file"),
    help="Location of the log file")
ARG_YES = Arg(
    ("-y", "--yes"),
    help="Do not prompt to confirm reset. Use with care!",
    action="store_true",
    default=False)
ARG_OUTPUT = Arg(
    ("--output",),
    help=(
        "Output table format. The specified value is passed to "
        "the tabulate module (https://pypi.org/project/tabulate/). "
    ),
    metavar="FORMAT",
    choices=tabulate_formats,
    default="plain")
ARG_COLOR = Arg(
    ('--color',),
    help="Do emit colored output (default: auto)",
    choices={ColorMode.ON, ColorMode.OFF, ColorMode.AUTO},
    default=ColorMode.AUTO)
ARG_DAG_ID_OPT = Arg(
    ("-d", "--dag-id"),