fix: use correct working-directory in action

Author: 0marperez

.github/actions/custom-gradle-distribution-url/action.yml

@@ -6,7 +6,7 @@ runs:
   using: composite
   steps:
     - name: Configure gradle distribution URL
-      working-directory: smithy-kotlin
+      working-directory: ./smithy-kotlin
       run: |
         # Keep gradle version in sync with smithy-kotlin/gradle/wrapper/gradle-wrapper.properties
         gradle wrapper --gradle-distribution-url https://d2pjps8lqszrgq.cloudfront.net/gradle-8.12-bin.zip