Bump setup-ruby to v1.270.0 (#1503)

The main goal is to fix doc generation build against `ruby/ruby`
([example](https://github.com/ruby/rdoc/actions/runs/20253167539/job/58149504928)).
But then I found that we can be more consistent on the `setup-ruby`
version across multiple workflows.

Author: st0012

.github/workflows/cloudflare-preview.yml

@@ -19,7 +19,7 @@ jobs:
           ref: ${{ github.event.client_payload.pr_head_sha }}
 
       - name: Setup Ruby
-        uses: ruby/setup-ruby@v1
+        uses: ruby/setup-ruby@ac793fdd38cc468a4dd57246fa9d0e868aba9085 # v1.270.0
         with:
           ruby-version: '3.4'
           bundler-cache: true

.github/workflows/gh-pages.yml

@@ -22,7 +22,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       - name: Setup Ruby
-        uses: ruby/setup-ruby@eaecf785f6a34567a6d97f686bbb7bccc1ac1e5c # v1.237.0
+        uses: ruby/setup-ruby@ac793fdd38cc468a4dd57246fa9d0e868aba9085 # v1.270.0
         with:
           ruby-version: '3.2'
           bundler-cache: true

.github/workflows/lint.yml

@@ -21,7 +21,7 @@ jobs:
     - if: ${{ matrix.os == 'ubuntu-latest' }}
       run: sudo apt install libyaml-dev
     - name: Set up Ruby
-      uses: ruby/setup-ruby@master
+      uses: ruby/setup-ruby@ac793fdd38cc468a4dd57246fa9d0e868aba9085 # v1.270.0
       with:
         ruby-version: 3.3
         bundler-cache: true

.github/workflows/push_gem.yml

@@ -30,7 +30,7 @@ jobs:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
 
       - name: Set up Ruby
-        uses: ruby/setup-ruby@eaecf785f6a34567a6d97f686bbb7bccc1ac1e5c # v1.237.0
+        uses: ruby/setup-ruby@ac793fdd38cc468a4dd57246fa9d0e868aba9085 # v1.270.0
         with:
           bundler-cache: true
           ruby-version: ruby

.github/workflows/ruby-core.yml

@@ -22,7 +22,7 @@ jobs:
     timeout-minutes: 30
     steps:
       - name: Set up latest ruby head
-        uses: ruby/setup-ruby@eaecf785f6a34567a6d97f686bbb7bccc1ac1e5c # v1.237.0
+        uses: ruby/setup-ruby@ac793fdd38cc468a4dd57246fa9d0e868aba9085 # v1.270.0
         with:
           ruby-version: head
           bundler: none

.github/workflows/test.yml

@@ -46,7 +46,7 @@ jobs:
     - if: ${{ matrix.os == 'ubuntu-latest' }}
       run: sudo apt install libyaml-dev
     - name: Set up Ruby
-      uses: ruby/setup-ruby@master
+      uses: ruby/setup-ruby@ac793fdd38cc468a4dd57246fa9d0e868aba9085 # v1.270.0
       with:
         ruby-version: ${{ matrix.ruby }}
         bundler-cache: true # 'bundle install' and cache