Bump actions/checkout to v5

Node 20 deprecation; v5 runs on Node 24.

beep boop

Author: khvn26

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ jobs:
     name: Lint + typecheck + unit tests
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           submodules: recursive
       - uses: astral-sh/setup-uv@v7
@@ -35,7 +35,7 @@ jobs:
       SNOWFLAKE_SCHEMA: ${{ secrets.SNOWFLAKE_SCHEMA }}
       SNOWFLAKE_PRIVATE_KEY_PATH: /tmp/snowflake_pk.p8
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           submodules: recursive
       - uses: astral-sh/setup-uv@v7