".../pg_cron.control": No such file or directory

Good day!
# ERROR
I got the following error restoring my database with `cron` schema in there:

```bash
... [100] ERROR: could not open extension control file "/usr/share/postgresql/12/extension/pg_cron.control": No such file or directory
... [100] STATEMENT: CREATE EXTENSION IF NOT EXISTS pg_cron WITH SCHEMA pg_catalog;
```
Then a bunch of related errors:
```bash
... [100] ERROR: extension "pg_cron" does not exist
... [100] STATEMENT: COMMENT ON EXTENSION pg_cron IS 'Job scheduler for PostgreSQL';

... [100] ERROR: schema "cron" does not exist
... [100] STATEMENT: COPY cron.job (jobid, schedule, command, nodename, nodeport, database, username, active, jobname) FROM stdin;

... [100] ERROR: schema "cron" does not exist
... [100] STATEMENT: COPY cron.job_run_details (jobid, runid, job_pid, database, username, command, status, return_message, start_time, end_time) FROM stdin;

... [100] ERROR: schema "cron" does not exist at character 26
... [100] STATEMENT: SELECT pg_catalog.setval('cron.jobid_seq', 2, true);
```
# Setup

I have a Kubernetes pod with the following configuration:
```yaml
spec:
containers:
- name: green-database
image: 'postgres:12.17'
imagePullPolicy: IfNotPresent
ports:
- containerPort: 5432
envFrom:
- configMapRef:
name: green-database-secret
resources:
limits:
cpu: 250m
memory: 256Mi
requests:
cpu: 250m
memory: 256Mi
volumeMounts:
- mountPath: /var/lib/postgresql/data
name: postgresdata
- name: operator
image: 'ubuntu'
imagePullPolicy: IfNotPresent
env:
- name: BLUE_URI
valueFrom:
secretKeyRef:
name: blue-postgres
key: database_uri
envFrom:
- configMapRef:
name: green-database-secret
command:
- "/bin/bash"
- "-c"
- |
apt-get update && apt-get upgrade -y
apt-get install -y curl gpg lsb-release systemctl openssh-server nano dnsutils
curl -fsSL https://www.postgresql.org/media/keys/ACCC4CF8.asc|gpg --dearmor -o /etc/apt/trusted.gpg.d/postgresql.gpg
echo "deb http://apt.postgresql.org/pub/repos/apt/ `lsb_release -cs`-pgdg main" |tee /etc/apt/sources.list.d/pgdg.list
apt-get update
DEBIAN_FRONTEND=noninteractive apt-get install -y postgresql-12 postgresql-client-12 postgresql-12-cron
echo "shared_preload_libraries = 'pg_cron'" >> /var/lib/postgresql/data/postgresql.conf
echo "cron.database_name = 'initial_db_name'" >> /var/lib/postgresql/data/postgresql.conf
/etc/init.d/postgresql restart && \
echo "Start Dumping data..."
pg_dump -d $BLUE_URI -w -c -C -Fc --if-exists -v > /tmp/blue.dump
dropdb initial_db_name
createdb -T template0 initial_db_name
# psql -d initial_db_name -c 'CREATE EXTENSION pg_cron;'
pg_restore -d initial_db_name -w -c -Fc --if-exists -v /tmp/blue.dump
echo "Start sleeping..."
tail -f /dev/null
resources:
limits:
cpu: 250m
memory: 256Mi
requests:
cpu: 250m
memory: 256Mi
volumeMounts:
- mountPath: /var/lib/postgresql/data
name: postgresdata
volumes:
- name: postgresdata
persistentVolumeClaim:
claimName: green-database-volume-claim
```

The last `operator` container log is:
```bash
pg_restore: from TOC entry 4428; 0 0 ACL TABLE job rds_superuser
pg_restore: error: could not execute query: ERROR: schema "cron" does not exist
Command was: REVOKE ALL ON TABLE cron.job FROM rdsadmin;
REVOKE SELECT ON TABLE cron.job FROM PUBLIC;
GRANT ALL ON TABLE cron.job TO rds_superuser;
GRANT SELECT ON TABLE cron.job TO PUBLIC;

pg_restore: creating ACL "cron.TABLE job_run_details"
pg_restore: from TOC entry 4429; 0 0 ACL TABLE job_run_details rds_superuser
pg_restore: error: could not execute query: ERROR: schema "cron" does not exist
Command was: REVOKE ALL ON TABLE cron.job_run_details FROM rdsadmin;
REVOKE SELECT,DELETE ON TABLE cron.job_run_details FROM PUBLIC;
GRANT ALL ON TABLE cron.job_run_details TO rds_superuser;
GRANT SELECT,DELETE ON TABLE cron.job_run_details TO PUBLIC;
```

I'm dumping RDS PostgreSQL 12.17 data and want to restore it in the pod. However, for some reason it can't restore `cron` schema.
I hope I can get some help here.
Thank you in advance!

Begin with the Kubernetes manifest and operator container command sequence, especially installation of postgresql-12-cron, shared_preload_libraries, and pg_restore. Reproduce the restore against PostgreSQL 12 and verify whether the pg_cron control file and cron schema are present; done means the failure is explained and the required setup or documentation change is identified.

Written by the indexing model from the issue text.