CI housekeeping

List of changes:
- bump GitHub Actions
- fix incorrect workflow triggers on wrong branch
- linting jobs only on Elixir 1.18/OTP 27
- remove unused jobs
- resolve Credo warnings
- support Elixir 1.18/OTP 27 CI matrix
- use short versions in CI matrix where setup/beam to auto expand to
  latest version

.github/workflows/ci.yaml

@@ -2,9 +2,9 @@ name: CI
 
 on:
   push:
-    branches: [ main ]
+    branches: [master]
   pull_request:
-    branches: [ main ]
+    branches: [master]
 
 jobs:
   check_duplicate_runs:
@@ -36,20 +36,23 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - elixir: "1.14.5"
-            otp: "24.3.4.17"
-          - elixir: "1.15.8-otp-25"
-            otp: "25.3.2.13"
-          - elixir: "1.16.3-otp-26"
-            otp: "26.2.5.2"
-          - elixir: "1.17.2-otp-27"
-            otp: "27.0.1"
+          - elixir: "1.14"
+            otp: "24"
+          - elixir: "1.15"
+            otp: "25"
+          - elixir: "1.16"
+            otp: "26"
+          - elixir: "1.17"
+            otp: "27"
+          - elixir: "1.18"
+            otp: "27"
+            lint: true
 
     runs-on: ubuntu-latest
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
 
     - name: Set up Elixir
       uses: erlef/setup-beam@v1
@@ -58,7 +61,7 @@ jobs:
         otp-version: ${{ matrix.otp }}
 
     - name: Restore deps and _build cache
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: |
           deps
@@ -72,7 +75,7 @@ jobs:
       run: mkdir -p priv/plts
 
     - name: Restore plts cache
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: priv/plts
         key: plts-${{ runner.os }}-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles('**/mix.lock') }}-${{ github.sha }}
@@ -85,9 +88,11 @@ jobs:
 
     - name: Check source code format
       run: mix format --check-formatted
+      if: ${{ matrix.lint }}
 
     - name: Perform source code static analysis
-      run: mix credo --strict
+      run: mix credo
+      if: ${{ matrix.lint }}
       env:
         MIX_ENV: test
 
@@ -105,21 +110,5 @@ jobs:
         MIX_ENV: test
 
     - name: Run tests
-      run: mix coveralls.github --warnings-as-errors
-      env:
-        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-    - name: Run dialyzer
-      run: mix dialyzer
-      env:
-        MIX_ENV: test
-
-  all_done:
-    name: Tests done
-    needs: tests
-
-    runs-on: ubuntu-latest
-
-    steps:
-    - name: All done
-      run: echo '+'
+      run: mix coveralls --warnings-as-errors
+      if: ${{ matrix.lint }}

mix.exs

@@ -44,7 +44,7 @@ defmodule JokenJwks.MixProject do
       {:telemetry, "~> 0.4.2 or ~> 1.0"},
 
       # docs
-      {:ex_doc, ">= 0.0.0", only: :dev, runtime: false},
+      {:ex_doc, ">= 0.0.0", only: [:dev, :test], runtime: false},
 
       # linters & coverage
       {:credo, "~> 1.7", only: [:dev, :test], runtime: false},