Fixup GleanPlumbMessageHelper rename bustage

app/src/androidTest/java/org/mozilla/fenix/helpers/Experimentation.kt

@@ -4,7 +4,7 @@
 
 package org.mozilla.fenix.helpers
 
-import org.mozilla.experiments.nimbus.GleanPlumbMessageHelper
+import org.mozilla.experiments.nimbus.NimbusMessagingHelperInterface
 import org.mozilla.fenix.ext.components
 import org.mozilla.fenix.helpers.TestHelper.appContext
 
@@ -12,7 +12,7 @@ object Experimentation {
     val experiments =
         appContext.components.analytics.experiments
 
-    fun withHelper(block: GleanPlumbMessageHelper.() -> Unit) {
+    fun withHelper(block: NimbusMessagingHelperInterface.() -> Unit) {
         val helper = experiments.createMessageHelper()
         block(helper)
     }