Add sqlite binary into the docker images

This is done to enable backup functionality in the admin interface while
we're waiting for the libsqlite-sys 0.17 to bubble up in the upstream
dependencies. Then we can start using `VACUUM INTO`

This also extends the check for the sqlite binary to also try `sqlite3`
as this is the name of the binary in baseimage distributions we use.

docker/amd64/postgresql/Dockerfile.alpine

@@ -64,6 +64,7 @@ RUN apk add --no-cache \
         openssl \
         postgresql-libs \
         curl \
+        sqlite \
         ca-certificates
 
 RUN mkdir /data