fuzz: Reuse go cache from host

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>

Author: Paulo Gomes

.github/workflows/cifuzz.yaml

@@ -13,12 +13,16 @@ jobs:
     steps:
     - name: Checkout
       uses: actions/checkout@v3
+    - name: Setup Go
+      uses: actions/setup-go@v3
+      with:
+        go-version: 1.18.x
     - name: Restore Go cache
       uses: actions/cache@v3
       with:
-        path: /home/runner/work/_temp/_github_home/go/pkg/mod
+        path: ~/go/pkg/mod
         key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
         restore-keys: |
-          ${{ runner.os }}-go-
+          ${{ runner.os }}-go
     - name: Smoke test Fuzzers
       run: make fuzz-smoketest

Makefile

@@ -155,6 +155,7 @@ fuzz-build:
 	docker run --rm \
 		-e FUZZING_LANGUAGE=go -e SANITIZER=address \
 		-e CIFUZZ_DEBUG='True' -e OSS_FUZZ_PROJECT_NAME=fluxcd \
+		-v "$(shell go env GOMODCACHE):/root/go/pkg/mod" \
 		-v "$(BUILD_DIR)/fuzz/out":/out \
 		local-fuzzing:latest