l10n: ci: disable cache for setup-go to suppress warnings

After we upgraded actions/setup-go to v5, the following warning message
was reported every time we ran the CI.

    Restore cache failed: Dependencies file is not found ...

Disable cache to suppress warning messages as described in the solution
below.

    actions/setup-go#427

Signed-off-by: Jiang Xin <worldhello.net@gmail.com>

Author: jiangxin

.github/workflows/l10n.yml

@@ -66,6 +66,7 @@ jobs:
       - uses: actions/setup-go@v5
         with:
           go-version: '>=1.16'
+          cache: false
       - name: Install git-po-helper
         run: go install github.com/git-l10n/git-po-helper@main
       - name: Install other dependencies