Expose the build configuration key through `ConfiguredObjectValue`.

PiperOrigin-RevId: 392535347
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/AspectValueKey.java b/src/main/java/com/google/devtools/build/lib/skyframe/AspectValueKey.java
index f97e08d..8ad02a8 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/AspectValueKey.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/AspectValueKey.java
@@ -218,7 +218,7 @@
      * base target's configuration.
      */
     @Nullable
-    BuildConfigurationValue.Key getAspectConfigurationKey() {
+    public BuildConfigurationValue.Key getAspectConfigurationKey() {
       return aspectConfigurationKey;
     }