.gradle.kts: more clear tooltip for out of project scripts notification

The current text/action/help text may not be clear: action is not related to project import, and help text doesn't make it clear.

#KT-36703 Fixed

idea/idea-gradle/src/org/jetbrains/kotlin/idea/scripting/gradle/GradleScriptOutOfSourceNotificationProvider.kt

@@ -32,7 +32,9 @@ class GradleScriptOutOfSourceNotificationProvider(private val project: Project)
             val link = createActionLabel("") {}
             link.setIcon(AllIcons.General.ContextHelp)
             link.setUseIconAsLink(true)
-            link.toolTipText = "Script configuration is used by IDE in highlighting, completion and other functionalities"
+            link.toolTipText = "The external Gradle project needs to be imported to get this script analyzed. <br/>" +
+                    "You can import the related Gradle project or click \"Load script configuration\" " +
+                    "to get code insight without importing."
         }
     }