Fix broken CI (#78)

.github/workflows/ci.yml

@@ -1,44 +1,39 @@
 name: CI
-
 on:
   pull_request:
   push:
     branches:
       - master
-
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
+    name: OTP ${{matrix.otp}} / Elixir ${{matrix.elixir}}
     env:
       MIX_ENV: test
     strategy:
       fail-fast: false
       matrix:
         include:
-          - pair:
-              elixir: 1.11.4
-              otp: 23.2
-            lint: lint
+        - elixir: '1.11.4'
+          otp: '23.3'
+        - elixir: '1.14.5'
+          otp: '24.3'
+        - elixir: '1.15.0'
+          otp: '26.0.1'
     steps:
       - uses: actions/checkout@v2
-
       - uses: erlef/setup-elixir@v1
         with:
-          otp-version: ${{matrix.pair.otp}}
-          elixir-version: ${{matrix.pair.elixir}}
-
+          otp-version: ${{matrix.otp}}
+          elixir-version: ${{matrix.elixir}}
+          version-type: strict
       - name: Install Dependencies
         run: mix deps.get --only test
-
       - run: mix format --check-formatted
         if: ${{ matrix.lint }}
-
       - run: mix deps.get && mix deps.unlock --check-unused
         if: ${{ matrix.lint }}
-
       - run: mix deps.compile
-
       - run: mix compile --warnings-as-errors
         if: ${{ matrix.lint }}
-
       - run: mix test