chore(deps): update actions/cache action to v6

Co-authored-by: Romuald Lemesl <romuald.lemesl@filigran.io>

Author: renovate[bot]

.github/workflows/agent-ci.yml

@@ -36,7 +36,7 @@ jobs:
           components: rustfmt
 
       - name: Cache
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: |
             ~/.cargo/bin/
@@ -100,7 +100,7 @@ jobs:
           components: clippy
 
       - name: Cache
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: |
             ~/.cargo/bin/
@@ -171,7 +171,7 @@ jobs:
           targets: ${{ matrix.target }}
 
       - name: Cache
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: |
             ~/.cargo/bin/
@@ -205,7 +205,7 @@ jobs:
           components: llvm-tools-preview
 
       - name: Cache
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: |
             ~/.cargo/bin/
@@ -297,7 +297,7 @@ jobs:
           targets: ${{ matrix.target }}
 
       - name: Cache
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: |
             ~/.cargo/bin/