Update to 6.0.0-rc.3, ghost-cli 1.28.2

Author: acburdine

6-rc/alpine/Dockerfile

@@ -47,7 +47,7 @@ RUN set -eux; \
 ENV GHOST_INSTALL /var/lib/ghost
 ENV GHOST_CONTENT /var/lib/ghost/content
 
-ENV GHOST_VERSION 6.0.0-rc.2
+ENV GHOST_VERSION 6.0.0-rc.3
 
 RUN set -eux; \
 	mkdir -p "$GHOST_INSTALL"; \

6-rc/debian/Dockerfile

@@ -43,7 +43,7 @@ RUN set -eux; \
 ENV GHOST_INSTALL /var/lib/ghost
 ENV GHOST_CONTENT /var/lib/ghost/content
 
-ENV GHOST_VERSION 6.0.0-rc.2
+ENV GHOST_VERSION 6.0.0-rc.3
 
 RUN set -eux; \
 	mkdir -p "$GHOST_INSTALL"; \