prep gosu for inclusion in pgpool

Dockerfile

@@ -29,20 +29,13 @@ RUN set -eux; \
 	locale -a | grep 'en_US.utf8'
 ENV LANG=en_US.utf8
 
-RUN set -ex; \
+ENV GOSU_VERSION=1.19
+RUN set -eux; \
 	apt-get update; \
 	apt-get install -y --no-install-recommends \
 		gnupg \
-		less \
-    	xz-utils \
-    	zstd \
 	   ; \
-	rm -rf /var/lib/apt/lists/*
-
-ENV GOSU_VERSION=1.19
-RUN set -eux; \
     savedAptMark="$(apt-mark showmanual)"; \
-	apt-get update; \
 	apt-get install -y --no-install-recommends \
             ca-certificates \
             wget \
@@ -63,6 +56,15 @@ RUN set -eux; \
 	gosu --version; \
 	gosu nobody true
 
+RUN set -ex; \
+	apt-get update; \
+	apt-get install -y --no-install-recommends \
+		less \
+    	xz-utils \
+    	zstd \
+	   ; \
+	rm -rf /var/lib/apt/lists/*
+
 RUN set -ex; \
 	key='B97B0AFCAA1A47F044F244A07FCC7D46ACCC4CF8'; \
 	export GNUPGHOME="$(mktemp -d)"; \