Switch CI to "latest" versions of Elixir and Erlang

Instead of using OTP master and Elixir main, use "latest" for all
linting checks. The version matrix does still include master/main.

.github/workflows/ci.yaml

@@ -21,8 +21,8 @@ jobs:
       - name: Set up Erlang and Elixir
         uses: erlef/setup-beam@v1
         with:
-          otp-version: master
-          elixir-version: main
+          otp-version: latest
+          elixir-version: latest
       - name: Checkout code
         uses: actions/checkout@v4
       - name: Check code formatting
@@ -34,8 +34,8 @@ jobs:
       - name: Set up Erlang and Elixir
         uses: erlef/setup-beam@v1
         with:
-          otp-version: master
-          elixir-version: main
+          otp-version: latest
+          elixir-version: latest
       - name: Checkout code
         uses: actions/checkout@v4
       - name: Get dependencies
@@ -49,8 +49,8 @@ jobs:
       - name: Set up Erlang and Elixir
         uses: erlef/setup-beam@v1
         with:
-          otp-version: master
-          elixir-version: main
+          otp-version: latest
+          elixir-version: latest
       - name: Checkout code
         uses: actions/checkout@v4
       - name: Get dependencies
@@ -87,8 +87,8 @@ jobs:
       - name: Set up Erlang and Elixir
         uses: erlef/setup-beam@v1
         with:
-          otp-version: master
-          elixir-version: main
+          otp-version: latest
+          elixir-version: latest
       - name: Set up Ruby
         uses: ruby/setup-ruby@v1
         with:
@@ -109,8 +109,8 @@ jobs:
       - name: Set up Erlang and Elixir
         uses: erlef/setup-beam@v1
         with:
-          otp-version: master
-          elixir-version: main
+          otp-version: latest
+          elixir-version: latest
       - name: Checkout code
         uses: actions/checkout@v4
       - name: Get dependencies