Fix truncateIdForDisplay and add test

libsession/src/main/java/org/session/libsession/utilities/IdUtil.kt

@@ -1,4 +1,4 @@
 package org.session.libsession.utilities
 
 fun truncateIdForDisplay(id: String): String =
-    id.takeIf { it.length > 8 }?.apply{ "${take(4)}…${takeLast(4)}" } ?: id
+    id.takeIf { it.length > 8 }?.run{ "${take(4)}…${takeLast(4)}" } ?: id

libsession/src/test/java/org/session/libsession/utilities/IdUtilTest.kt

@@ -0,0 +1,25 @@
+package org.session.libsession.utilities
+
+import org.junit.Assert
+import org.junit.Test
+
+class IdUtilTest {
+
+    @Test
+    fun testTruncate() {
+        val testString = "123456789"
+
+        val result = truncateIdForDisplay(testString)
+
+        Assert.assertEquals(result, "1234…6789")
+    }
+
+    @Test
+    fun testDontTruncateShortMessage() {
+        val testString = "not much"
+
+        val result = truncateIdForDisplay(testString)
+
+        Assert.assertEquals(result, "not much")
+    }
+}