Bump ruby/setup-ruby from 1.281.0 to 1.284.0 (getmoto#9657)

Author: dependabot[bot]

.github/workflows/tests_sdk_ruby.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
       - uses: actions/checkout@v6
       - name: Set up Ruby ${{ matrix.ruby-version }}
-        uses: ruby/setup-ruby@675dd7ba1b06c8786a1480d89c384f5620a42647
+        uses: ruby/setup-ruby@80740b3b13bf9857e28854481ca95a84e78a2bdf
         with:
           ruby-version: ${{ matrix.ruby-version }}
       - name: Set up Python 3.12