Improve on "Add Windows to the mix" (#52)

* Support more OTP+Windows versions (try to bridge the gap with gleam-lang/setup-erlang that seems to support pre-21 versions)
* Merge ci.yml and test.yml
* Add Elixir to the Windows mix
* Hopefully improve error/warning messages
* Adapt the doc.s to the current reality
* Add option version-type (loose by default, for compatibility)

src/install-elixir.sh

@@ -9,12 +9,8 @@ FILE_INPUT="${VSN}.zip"
 FILE_OUTPUT=elixir.zip
 DIR_FOR_BIN=.setup-beam/elixir
 
-rm -f "${FILE_OUTPUT}"
-rm -rf "${DIR_FOR_BIN}"
 wget -q -O "${FILE_OUTPUT}" "https://repo.hex.pm/builds/elixir/${FILE_INPUT}"
 mkdir -p "${DIR_FOR_BIN}"
 unzip -q -d "${DIR_FOR_BIN}" "${FILE_OUTPUT}"
-rm -f "${FILE_OUTPUT}"
-echo "$(pwd)/${DIR_FOR_BIN}/bin" >> "$GITHUB_PATH"
 echo "Installed Elixir version follows"
 ${DIR_FOR_BIN}/bin/iex -v