Fix gosu errors regarding gpg key management

Author: aarranz

1.0-composable/Dockerfile

@@ -18,7 +18,7 @@ RUN apt update && \
                             keyserver.ubuntu.com \
                             hkp://keyserver.ubuntu.com:80 \
                             pgp.mit.edu) ; do \
-        gpg --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
+        gpg --batch --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
     done && \
     gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu && \
     rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc && \

1.1-composable/Dockerfile

@@ -18,7 +18,7 @@ RUN apt update && \
                             keyserver.ubuntu.com \
                             hkp://keyserver.ubuntu.com:80 \
                             pgp.mit.edu) ; do \
-        gpg --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
+        gpg --batch --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
     done && \
     gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu && \
     rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc && \

1.2/Dockerfile

@@ -21,7 +21,7 @@ RUN apt-get update && \
                             keyserver.ubuntu.com \
                             hkp://keyserver.ubuntu.com:80 \
                             pgp.mit.edu) ; do \
-        gpg --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
+        gpg --batch --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
     done && \
     gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu && \
     rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc && \

dev/Dockerfile

@@ -20,7 +20,7 @@ RUN apt-get update && \
                             keyserver.ubuntu.com \
                             hkp://keyserver.ubuntu.com:80 \
                             pgp.mit.edu) ; do \
-        gpg --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
+        gpg --batch --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
     done && \
     gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu && \
     rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc && \