chore(docker): bump gosu to 1.19

Update gosu from version 1.16 to 1.19 in Dockerfile-15, Dockerfile-17, and Dockerfile-orioledb-17.

This change aligns the Docker images with the official Docker Postgres image,
which recently upgraded to gosu 1.19. Staying consistent with the upstream
helps reduce potential security findings and maintain compatibility with
the official base images.

A Trivy scan on the previous image reported several medium to critical
issues in the older gosu binary. Updating to the latest version helps
minimize these potential risks.

No functional changes beyond the version update.

Author: ImreSamu

Dockerfile-15

@@ -134,7 +134,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
    ca-certificates \
    && rm -rf /var/lib/apt/lists/*
 # Download binary
-ARG GOSU_VERSION=1.16
+ARG GOSU_VERSION=1.19
 ARG GOSU_GPG_KEY=B42F6819007F00F88E364FD4036A9C25BF357DD4
 ADD https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$TARGETARCH \
     /usr/local/bin/gosu

Dockerfile-17

@@ -138,7 +138,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
    ca-certificates \
    && rm -rf /var/lib/apt/lists/*
 # Download binary
-ARG GOSU_VERSION=1.16
+ARG GOSU_VERSION=1.19
 ARG GOSU_GPG_KEY=B42F6819007F00F88E364FD4036A9C25BF357DD4
 ADD https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$TARGETARCH \
     /usr/local/bin/gosu

Dockerfile-orioledb-17

@@ -138,7 +138,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
    ca-certificates \
    && rm -rf /var/lib/apt/lists/*
 # Download binary
-ARG GOSU_VERSION=1.16
+ARG GOSU_VERSION=1.19
 ARG GOSU_GPG_KEY=B42F6819007F00F88E364FD4036A9C25BF357DD4
 ADD https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$TARGETARCH \
     /usr/local/bin/gosu