ci: update actions

Author: MilesCranmer

.github/workflows/CI.yml

@@ -39,13 +39,13 @@ jobs:
             julia-version: '1.10'
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: "Set up Julia"
-        uses: julia-actions/setup-julia@v1
+        uses: julia-actions/setup-julia@v2
         with:
           version: ${{ matrix.julia-version }}
       - name: "Cache artifacts"
-        uses: julia-actions/cache@v1
+        uses: julia-actions/cache@v2
       - name: "Build package"
         uses: julia-actions/julia-buildpkg@v1
       - name: "Run tests"
@@ -75,11 +75,11 @@ jobs:
           # - "enzyme"  # flaky; seems to infinitely compile and fail the CI
           - "jet"
     steps:
-      - uses: actions/checkout@v2
-      - uses: julia-actions/setup-julia@v1
+      - uses: actions/checkout@v4
+      - uses: julia-actions/setup-julia@v2
         with:
           version: ${{ matrix.julia-version }}
-      - uses: julia-actions/cache@v1
+      - uses: julia-actions/cache@v2
       - uses: julia-actions/julia-buildpkg@v1
       - name: Run tests
         id: run-tests