Update ruby/setup-ruby action to v1.278.0 (#734)

This PR contains the following updates:

| Package | Type | Update | Change | Pending |
|---|---|---|---|---|
| [ruby/setup-ruby](https://redirect.github.com/ruby/setup-ruby) |
action | minor | `v1.277.0` → `v1.278.0` | `v1.280.0` (+1) |

---

### Release Notes

<details>
<summary>ruby/setup-ruby (ruby/setup-ruby)</summary>

###
[`v1.278.0`](https://redirect.github.com/ruby/setup-ruby/releases/tag/v1.278.0)

[Compare
Source](https://redirect.github.com/ruby/setup-ruby/compare/v1.277.0...v1.278.0)

#### What's Changed

- Set BUNDLER\_VERSION whenever we know which version to use by
[@&#8203;eregon](https://redirect.github.com/eregon) in
[#&#8203;849](https://redirect.github.com/ruby/setup-ruby/pull/849)

**Full Changelog**:
<ruby/setup-ruby@v1.277.0...v1.278.0>

</details>

---

### Configuration

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rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
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---

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---

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.github/workflows/deploy-doc.yml

@@ -17,7 +17,7 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
-      - uses: ruby/setup-ruby@8a836efbcebe5de0fe86b48a775b7a31b5c70c93 # v1.277.0
+      - uses: ruby/setup-ruby@4c24fa5ec04b2e79eb40571b1cee2a0d2b705771 # v1.278.0
         with:
           ruby-version: '4.0.0'
       - run: bundle install

.github/workflows/publish.yml

@@ -20,7 +20,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
-      - uses: ruby/setup-ruby@8a836efbcebe5de0fe86b48a775b7a31b5c70c93 # v1.277.0
+      - uses: ruby/setup-ruby@4c24fa5ec04b2e79eb40571b1cee2a0d2b705771 # v1.278.0
         with:
           bundler-cache: true
           ruby-version: 4.0.0

.github/workflows/pull_request.yml

@@ -23,7 +23,7 @@ jobs:
     - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       with:
         submodules: true
-    - uses: ruby/setup-ruby@8a836efbcebe5de0fe86b48a775b7a31b5c70c93 # v1.277.0
+    - uses: ruby/setup-ruby@4c24fa5ec04b2e79eb40571b1cee2a0d2b705771 # v1.278.0
       with:
         ruby-version: ${{ matrix.ruby }}
     - uses: actions/setup-java@f2beeb24e141e01a676f977032f5a29d81c9e27e # v5.1.0