Pre-emptively update a few more version numbers to 1.13

Author: tianon

INSTALL.md

@@ -18,7 +18,7 @@ RUN set -eux; \
 Older Debian releases (or newer `gosu` releases):
 
 ```dockerfile
-ENV GOSU_VERSION 1.12
+ENV GOSU_VERSION 1.13
 RUN set -eux; \
 # save list of currently installed packages for later so we can clean up
 	savedAptMark="$(apt-mark showmanual)"; \
@@ -59,7 +59,7 @@ RUN set -eux; \
 **Note:** when using Alpine, it's probably also worth checking out [`su-exec`](https://github.com/ncopa/su-exec) (`apk add --no-cache su-exec`) instead, which since version 0.2 is fully `gosu`-compatible in a fraction of the file size.
 
 ```dockerfile
-ENV GOSU_VERSION 1.12
+ENV GOSU_VERSION 1.13
 RUN set -eux; \
 	\
 	apk add --no-cache --virtual .gosu-deps \

hub/Dockerfile.alpine

@@ -1,7 +1,7 @@
 FROM alpine:3.13
 
 # https://github.com/tianon/gosu/releases
-ENV GOSU_VERSION 1.12
+ENV GOSU_VERSION 1.13
 
 RUN set -eux; \
 	apk add --no-cache --virtual .fetch-deps dpkg gnupg; \

hub/Dockerfile.debian

@@ -1,7 +1,7 @@
 FROM debian:buster-slim
 
 # https://github.com/tianon/gosu/releases
-ENV GOSU_VERSION 1.12
+ENV GOSU_VERSION 1.13
 
 RUN set -eux; \
 	savedAptMark="$(apt-mark showmanual)"; \