Fix fontcustom (#73)

Author: TWiStErRob

.github/workflows/install-fontcustom.sh

@@ -1,13 +1,33 @@
+set -eo pipefail
+
 mkdir -p fontcustom && cd fontcustom
+
+# Workaround for
+# > Error installing fontcustom:
+# > The last version of ffi (~> 1.0) to support your Ruby & RubyGems was 1.17.0.
+# > Try installing it with `gem install ffi -v 1.17.0` and then running the current command again
+# > ffi requires RubyGems version >= 3.3.22. The current RubyGems version is 3.1.6.
+# > Try 'gem update --system' to update RubyGems itself.
+# As an additional workaround for "gem update --system" erroring with:
+# > Error installing rubygems-update:
+# > There are no versions of rubygems-update (= 3.5.14) compatible with your Ruby & RubyGems
+# > rubygems-update requires Ruby version >= 3.0.0. The current ruby version is 2.7.8.225.
+# downgrading to specific version because Rubygems 3.5 dropped support for Ruby 2.7.x
+# https://blog.rubygems.org/2023/12/15/3.5.0-released.html
+gem update --system 3.4.22
+
 gem install fontcustom --version 2.0.0
+
 sudo apt-get install fontforge=1:20201107~dfsg-4build1
-git clone --branch v1.3.1 --depth 1 https://github.com/bramstein/sfnt2woff-zopfli.git \
+
+git -c advice.detachedHead=false clone --branch v1.3.1 --depth 1 https://github.com/bramstein/sfnt2woff-zopfli.git \
   && pushd sfnt2woff-zopfli \
   && make \
   && mv sfnt2woff-zopfli sfnt2woff \
   && echo "${PWD}" >> "${GITHUB_PATH}" \
   && popd
-git clone --branch v1.0.2 --depth 1 --recursive https://github.com/google/woff2.git \
+
+git -c advice.detachedHead=false clone --branch v1.0.2 --depth 1 --recursive https://github.com/google/woff2.git \
   && pushd woff2 \
   && make clean all \
   && echo "${PWD}" >> "${GITHUB_PATH}" \