ci: prevent error if rust build is cached by nx (#4951)

If Rust build was cached by nx, only the output file will be presented. The chmod command will be failed in this case like: https://github.com/toeverything/AFFiNE/actions/runs/6874496337/job/18697360212

.github/actions/build-rust/action.yml

@@ -51,8 +51,12 @@ runs:
           export CC_x86_64_unknown_linux_gnu=x86_64-unknown-linux-gnu-gcc
           export RUSTFLAGS="-C debuginfo=1"
           yarn workspace ${{ inputs.package }} nx build ${{ inputs.package }} --target ${{ inputs.target }}
-          chmod -R 777 node_modules/.cache
-          chmod -R 777 target
+          if [ -d "node_modules/.cache" ]; then
+            chmod -R 777 node_modules/.cache
+          fi
+          if [ -d "target" ]; then
+            chmod -R 777 target;
+          fi
 
     - name: Build
       if: ${{ inputs.target == 'aarch64-unknown-linux-gnu' }}
@@ -63,5 +67,9 @@ runs:
         run: |
           export RUSTFLAGS="-C debuginfo=1"
           yarn workspace ${{ inputs.package }} nx build ${{ inputs.package }} --target ${{ inputs.target }}
-          chmod -R 777 node_modules/.cache
-          chmod -R 777 target
+          if [ -d "node_modules/.cache" ]; then
+            chmod -R 777 node_modules/.cache
+          fi
+          if [ -d "target" ]; then
+            chmod -R 777 target;
+          fi