Update actions/cache digest to 6849a64 (#1575)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/cache](https://redirect.github.com/actions/cache) | action |
digest | `3624ceb` -> `6849a64` |

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.github/workflows/ci.yml

@@ -35,7 +35,7 @@ jobs:
 
       - name: Cache zed-extension CLI
         id: cache-zed-extension
-        uses: actions/cache@3624ceb22c1c5a301c8db4169662070a689d9ea8 # v4
+        uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4
         with:
           path: |
             zed-extension
@@ -57,7 +57,7 @@ jobs:
         run: pnpm test
 
       - name: Cache extension build dependencies
-        uses: actions/cache@3624ceb22c1c5a301c8db4169662070a689d9ea8 # v4
+        uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4
         with:
           key: cache-build-dependencies
           path: |