Update for latest Gleam (#138)

* Update for latest Gleam

- Gleam releases now use LLVM triplets for platforms so the download
  URLs have been updated accordingly.
- Gleam's rebar3 support has been removed.

This change means that future versions of this action cannot download
older versions of Gleam. I can make it backwards compatible, but I will
need help from someone who can convert the shell script into PowerShell
for Windows.

* Support older Gleam versions

* Remove rebar from Gleam

.github/workflows/windows.yml

@@ -41,7 +41,7 @@ jobs:
             otp-version: '24'
             rebar3-version: '3.15'
             os: 'windows-latest'
-          - gleam-version: '0.16'
+          - gleam-version: '0.23.0-rc1'
             otp-version: '24'
             rebar3-version: '3.16'
             os: 'windows-latest'
@@ -82,11 +82,6 @@ jobs:
           cd test-projects/erlang_rebar3
           rebar3 ct
         if: ${{matrix.combo.rebar3-version}}
-      - name: Run Gleam/rebar3 project tests
-        run: |
-          cd test-projects/gleam_rebar3
-          rebar3 eunit
-        if: ${{matrix.combo.gleam-version}}
   environment_variables:
     name: Environment variables
     runs-on: ${{matrix.combo.os}}
@@ -96,7 +91,7 @@ jobs:
         combo:
           - otp-version: '24'
             elixir-version: 'v1.12'
-            gleam-version: '0.19'
+            gleam-version: '0.23.0-rc1'
             rebar3-version: 'nightly'
             os: 'windows-latest'
     steps: