Problem when installing pg_cron. Can you help me fix my Dockerfile?

I know this is a very common error when installing pg_cron but I cannot make it work even after reading.

i get this error when i run "CREATE EXTENSION pg_cron;"

ERROR: unrecognized configuration parameter "cron.database_name"
CONTEXT: PL/pgSQL function inline_code_block line 3 at IF

SQL state: 42704

my Dockerfile looks like this (i created an image of postgres with postgis, pgvector and cron all extensions work bu cron).

`
FROM postgres:15

ENV POSTGRES_DB mydatabase
ENV POSTGRES_USER myuser
ENV POSTGRES_PASSWORD mypassword

# Update package lists
RUN apt-get update

# Install PostgreSQL extensions
RUN apt-get install -y --no-install-recommends \
postgresql-contrib \
postgresql-15-pgvector \
postgresql-15-cron \
postgresql-15-postgis

# Create a custom configuration file
RUN mkdir -p /var/lib/postgresql/data/conf.d \
&& echo "shared_preload_libraries = 'pg_cron'" > /var/lib/postgresql/data/conf.d/pg_cron.conf \
&& echo "cron.database_name = 'mydatabase'" >> /var/lib/postgresql/data/conf.d/pg_cron.conf \
&& chown -R postgres:postgres /var/lib/postgresql/data/conf.d

# Include the custom configuration file
RUN echo "include_dir = '/var/lib/postgresql/data/conf.d'" >> /var/lib/postgresql/data/postgresql.conf

# Clean up
RUN apt-get clean && rm -rf /var/lib/apt/lists/*

# Expose the PostgreSQL port
EXPOSE 5432
`

Start with the Dockerfile configuration for shared_preload_libraries, cron.database_name, and the postgresql.conf include_dir shown in the issue. Reproduce the image and inspect the running PostgreSQL configuration before running CREATE EXTENSION pg_cron. Done means the cron.database_name parameter is recognized and the extension can be created successfully.

Written by the indexing model from the issue text.