Update deploy-branches.yml (try clearing cache first)

Author: dm0n3y

.github/workflows/deploy-branches.yml

@@ -16,6 +16,8 @@ jobs:
           path: source
       - name: Add name of current branch to environment as BRANCH_NAME
         uses: nelonoel/branch-name@v1.0.1
+      - name: Clear opam cache
+        run: rm -rf /home/runner/.opam/        
       - name: Retrieve build environment if cached # STEP 2
         id: opam-cache
         uses: actions/cache@v4