Use non-root path as it caused some issues

Author: mattlord

Dockerfile

@@ -1,13 +1,11 @@
 FROM debian:10-slim
 RUN apt-get update \
-    && apt-get -y install socat ca-certificates \
+    && apt-get -y install ca-certificates \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists
 
-ARG binary
-
-COPY bin/postgres_exporter /postgres_exporter
+COPY bin/postgres_exporter /usr/bin/postgres_exporter
 
 EXPOSE 9187
 
-ENTRYPOINT [ "/postgres_exporter" ]
+ENTRYPOINT [ "/usr/bin/postgres_exporter" ]