Could not open extension control file “/usr/share/postgresql/10/extension/pg_similarity.control”: No such file or directory - Mailing list pgsql-general

FROM postgres:10

ENV POSTGRES_USER user
ENV POSTGRES_PASSWORD user
ENV POSTGRES_DB user_db

RUN apt-get update \   && apt-get upgrade -y \   && apt-get -y install \    postgresql-server-dev-all \    wget \    make \    gcc \   && rm -rf /var/lib/apt/lists/*
RUN wget -c 'pgfoundry.org/frs/download.php/2237/pg_similarity-0.0.19.tgz' 
RUN tar -zxf pg_similarity-0.0.19.tgz
RUN cd pg_similarity \   && USE_PGXS=1 make \   && USE_PGXS=1 make install

Then I build the image and I run the container. I exec into the container:

psql -U user -d user_db
psql (10.3 (Debian 10.3-1.pgdg90+1))Type "help" for help.
user_db=# create extension pg_similarity;

ERROR: could not open extension control file "/usr/share/postgresql/10/extension/pg_similarity.control": No such file or directory

Under /usr/share/postgres/10/contrib I find the file pg_similarity.sql.How can I fix this problem?