test: migrate SnippetTest to JUnit 5 (#4461)

src/test/java/spoon/test/snippets/SnippetTest.java

@@ -16,19 +16,19 @@
  */
 package spoon.test.snippets;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import spoon.Launcher;
 import spoon.compiler.SpoonResource;
 import spoon.reflect.code.CtBinaryOperator;
+import spoon.reflect.code.CtBlock;
 import spoon.reflect.code.CtCodeSnippetExpression;
 import spoon.reflect.code.CtCodeSnippetStatement;
+import spoon.reflect.code.CtComment;
 import spoon.reflect.code.CtExpression;
 import spoon.reflect.code.CtInvocation;
 import spoon.reflect.code.CtLocalVariable;
 import spoon.reflect.code.CtReturn;
 import spoon.reflect.code.CtStatement;
-import spoon.reflect.code.CtBlock;
-import spoon.reflect.code.CtComment;
 import spoon.reflect.declaration.CtClass;
 import spoon.reflect.declaration.CtElement;
 import spoon.reflect.declaration.CtMethod;
@@ -38,13 +38,14 @@
 import spoon.support.compiler.SnippetCompilationHelper;
 import spoon.support.compiler.VirtualFile;
 
+
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertSame;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.fail;
 import static spoon.testing.utils.ModelUtils.createFactory;
 
 public class SnippetTest {