chore: bump actions/checkout GitHub Actions (#193)

## Summary

CI:
- Update [actions/checkout](https://github.com/actions/checkout)
references from the previous v4 commit SHA to the new
[v5](https://github.com/actions/checkout/releases/tag/v5.0.0) commit SHA
in all workflow files

Author: マルコメ

.github/workflows/gemini-issue-automated-triage.yml

@@ -43,7 +43,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     steps:
       - name: 'Checkout repository'
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
 
       - name: 'Generate GitHub App Token'
         id: 'generate_token'

.github/workflows/gemini-issue-scheduled-triage.yml

@@ -25,7 +25,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     steps:
       - name: 'Checkout repository'
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
 
       - name: 'Generate GitHub App Token'
         id: 'generate_token'

.github/workflows/gemini-pr-review.yml

@@ -76,7 +76,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     steps:
       - name: 'Checkout PR code'
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
 
       - name: 'Generate GitHub App Token'
         id: 'generate_token'

.github/workflows/publish.yml

@@ -16,7 +16,7 @@ jobs:
 
     steps:
       - name: 'Checkout'
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
 
       - name: 'Publish'
         id: 'publish'

examples/workflows/gemini-cli/gemini-cli.yml

@@ -126,7 +126,7 @@ jobs:
       - name: 'Checkout PR branch'
         if: |-
           ${{  steps.get_context.outputs.is_pr == 'true' }}
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
         with:
           token: '${{ steps.generate_token.outputs.token || secrets.GITHUB_TOKEN }}'
           repository: '${{ github.repository }}'
@@ -136,7 +136,7 @@ jobs:
       - name: 'Checkout main branch'
         if: |-
           ${{  steps.get_context.outputs.is_pr == 'false' }}
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
         with:
           token: '${{ steps.generate_token.outputs.token || secrets.GITHUB_TOKEN }}'
           repository: '${{ github.repository }}'

examples/workflows/issue-triage/gemini-issue-automated-triage.yml

@@ -43,7 +43,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     steps:
       - name: 'Checkout repository'
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
 
       - name: 'Generate GitHub App Token'
         id: 'generate_token'

examples/workflows/issue-triage/gemini-issue-scheduled-triage.yml

@@ -25,7 +25,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     steps:
       - name: 'Checkout repository'
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
 
       - name: 'Generate GitHub App Token'
         id: 'generate_token'

examples/workflows/pr-review/gemini-pr-review.yml

@@ -76,7 +76,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     steps:
       - name: 'Checkout PR code'
-        uses: 'actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # ratchet:actions/checkout@v4
+        uses: 'actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8' # ratchet:actions/checkout@v5
 
       - name: 'Generate GitHub App Token'
         id: 'generate_token'