Update actions/checkout action from vv4 to v6 (#258)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/deploy.yml

@@ -12,7 +12,7 @@ jobs:
     outputs:
       version: ${{ steps.get-version.outputs.version }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - name: Install xmlstarlet

.github/workflows/gitflow-hotfix-finish.yml

@@ -65,7 +65,7 @@ jobs:
     outputs:
       version: ${{ steps.get_version.outputs.version }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.hotfix_branch }}
           fetch-depth: 0
@@ -89,7 +89,7 @@ jobs:
     needs: get-hotfix-version
     runs-on: ${{ inputs.runner || 'ubuntu-24.04' }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.hotfix_branch }}
           fetch-depth: 0
@@ -123,7 +123,7 @@ jobs:
       JRELEASER_UPDATE: true
       JRELEASER_GIT_ROOT_SEARCH: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.version_tag_prefix || 'v' }}${{ needs.get-hotfix-version.outputs.version }}
           fetch-depth: 0
@@ -170,7 +170,7 @@ jobs:
     if: inputs.merge_to_main == true
     runs-on: ${{ inputs.runner || 'ubuntu-24.04' }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.base_branch || 'main' }}
           fetch-depth: 0

.github/workflows/gitflow-release-finish.yml

@@ -69,7 +69,7 @@ jobs:
     outputs:
       version: ${{ steps.get_version.outputs.version }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.release_branch }}
           fetch-depth: 0
@@ -93,7 +93,7 @@ jobs:
     needs: get-release-version
     runs-on: ${{ inputs.runner || 'ubuntu-24.04' }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.release_branch }}
           fetch-depth: 0
@@ -127,7 +127,7 @@ jobs:
       JRELEASER_UPDATE: true
       JRELEASER_GIT_ROOT_SEARCH: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.version_tag_prefix || 'v' }}${{ needs.get-release-version.outputs.version }}
           fetch-depth: 0
@@ -173,7 +173,7 @@ jobs:
     needs: [get-release-version, publish-release]
     runs-on: ${{ inputs.runner || 'ubuntu-24.04' }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.base_branch || 'main' }}
           fetch-depth: 0
@@ -200,7 +200,7 @@ jobs:
     needs: [get-release-version, merge-release-to-base]
     runs-on: ${{ inputs.runner || 'ubuntu-24.04' }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ inputs.base_branch || 'main' }}
           fetch-depth: 0

.github/workflows/hotfix-manual.yml

@@ -30,7 +30,7 @@ jobs:
       JRELEASER_UPDATE: true
       JRELEASER_GIT_ROOT_SEARCH: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ github.event.inputs.git_ref }}
           fetch-depth: 0

.github/workflows/maven-jreleaser-release.yml

@@ -94,14 +94,14 @@ jobs:
       version: ${{ steps.release.outputs.version }}
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         if: ${{ inputs.git_ref == '' }}
         with:
           fetch-depth: 0
           ssh-key: ${{ secrets.GIT_SSH_KEY }}
 
       - name: Checkout code with reference
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         if: ${{ inputs.git_ref != '' }}
         with:
           ref: ${{ inputs.git_ref }}

.github/workflows/release-manual.yml

@@ -30,7 +30,7 @@ jobs:
       JRELEASER_UPDATE: true
       JRELEASER_GIT_ROOT_SEARCH: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ github.event.inputs.git_ref }}
           fetch-depth: 0