Update Renovatebot GHA Updates to v6 (#128)

Co-authored-by: protocols-renovate[bot] <270912179+protocols-renovate[bot]@users.noreply.github.com>

Author: protocols-renovate[bot]

.github/workflows/test_docker_image_sanitize_input.yml

@@ -25,7 +25,7 @@ jobs:
           - 'custom_image.name:v1.0.0-beta'
     steps:
       - name: Checkout Code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
 
       # Run the action. If it fails, the job naturally stops and turns red.
       - name: Validate String
@@ -62,7 +62,7 @@ jobs:
           - 'registry.com/image:INVALID_TAG_!!!!'   # Violates regex character limits
     steps:
       - name: Checkout Code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
 
       # continue-on-error prevents the bad string from instantly halting the job,
       # allowing us to test its exit status in the next step.

java-setup-gradle/action.yml

@@ -22,6 +22,5 @@ runs:
         java-version: ${{ inputs.VERSION }}
         distribution: '${{ inputs.DISTRIBUTION }}'
 
-    # v5.0.2
     - name: Setup Gradle
       uses: gradle/actions/setup-gradle@39e147cb9de83bb9910b8ef8bd7fff0ee20fcd6f # v6.0.1