Done make-abbreviation task

Author: VitaliyProgrammer

build.gradle.kts

@@ -20,7 +20,7 @@ tasks.test {
 }
 
 kotlin {
-    jvmToolchain(11)
+    jvmToolchain(17)
 }
 
 application {

src/main/kotlin/mate/academy/MakeAbbreviation.kt

@@ -1,6 +1,8 @@
 package mate.academy
 
-fun makeAbbr(source: String) : String {
-    // implement this function
-    return ""
+fun makeAbbr(source: String): String {
+
+    return source
+        .split(" ")
+        .joinToString("") { it.first().uppercase() }
 }