test: migrate to JUnit 5 (PR #493)

jadx-gui/src/test/java/jadx/gui/treemodel/JSourcesTest.java

@@ -3,8 +3,8 @@ package jadx.gui.treemodel;
 import java.util.Collections;
 import java.util.List;
 
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 import jadx.api.Factory;
 import jadx.api.JadxArgs;
@@ -26,7 +26,7 @@ public class JSourcesTest {
 	private JSources sources;
 	private JadxDecompiler decompiler;
 
-	@Before
+	@BeforeEach
 	public void init() {
 		JRoot root = mock(JRoot.class);
 		when(root.isFlatPackages()).thenReturn(false);

jadx-gui/src/test/java/jadx/gui/utils/CertificateManagerTest.java

@@ -8,8 +8,8 @@ import java.security.cert.Certificate;
 import java.util.Collection;
 
 import org.junit.Assert;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 public class CertificateManagerTest {
 	private static final String CERTIFICATE_TEST_DIR = "certificate-test/";
@@ -32,7 +32,7 @@ public class CertificateManagerTest {
 		}
 	}
 
-	@Before
+	@BeforeEach
 	public void setUp() {
 		emptyPath = getResourcePath(EMPTY);
 		certificateManagerRSA = getCertificateManger(RSA);