tmp not writable

[dignakov]

Hi,

I was trying to build the image with the latest version of Grav. Following #11, I added the apk update and apk upgrade lines to the install script:

# PHP EXTENSIONS!
#
# Add any php extensions your application needs.  Alpine Linux is VERY granular and
# does not contain the large number of extensions you'd expect in a Ubuntu/Debian/CentOS
# install.  You can find the package names here...
# https://pkgs.alpinelinux.org/packages?name=php-%25&repo=all&arch=x86_64&maintainer=all

# >>>>>>>>>>> THIS IS NEW  <<<<<<<<<<
apk update
apk upgrade
# >>>>>>>>>>> THIS IS NEW  <<<<<<<<<<

apk --update add \
    php-ctype \
    php-curl \
    php-dom \

and built the image. However when I run ./run-docker-grav.sh -s ./testsite, I get an error saying:

/apps/www/grav/tmp exists but is not writeable

Any idea what I'm doing wrong?