Update gradle/actions action to v6

Author: renovate[bot]

.github/workflows/gradle-wrapper-validation.yml

@@ -7,4 +7,4 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@08eba0b27e820071cde6df949e0beb9ba4906955 # v4
-      - uses: gradle/actions/wrapper-validation@748248ddd2a24f49513d8f472f81c3a07d4d50e1 # v4
+      - uses: gradle/actions/wrapper-validation@50e97c2cd7a37755bbfafc9c5b7cafaece252f6e # v6