mdu.edu.rs is not educational domain

lib/domains/blacklist.txt

@@ -13,3 +13,4 @@ sharif.ir
 sharif.edu
 my.edu.moi
 art.edu.lv
+mdu.edu.rs

test/swot/SwotTest.kt

@@ -43,6 +43,7 @@ class SwotTest : TestCase() {
         assertEquals (true , isAcademic("lee@mail.harvard.edu"))
 
         assertEquals(false, isAcademic("imposter@si.edu"))
+        assertEquals(false, isAcademic("lee@mdu.edu.rs"))
 
         // Iran sanctions are lifted
         assertEquals(true, isAcademic("lee@acmt.ac.ir"))