com.rarchives.ripme.tst from junit3 to junit5

AppTest is not migrated as it only does true=true, otherwise it is not
clear what this should be.

src/test/java/com/rarchives/ripme/tst/AbstractRipperTest.java

@@ -1,15 +1,17 @@
 package com.rarchives.ripme.tst;
 
 import com.rarchives.ripme.ripper.AbstractRipper;
-import junit.framework.TestCase;
+import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
 import java.net.URL;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 
-public class AbstractRipperTest extends TestCase {
+public class AbstractRipperTest {
 
+   @Test
     public void testGetFileName() throws IOException {
        String fileName = AbstractRipper.getFileName(new URL("http://www.tsumino.com/Image/Object?name=U1EieteEGwm6N1dGszqCpA%3D%3D"), "test", "test");
        assertEquals("test.test", fileName);

src/test/java/com/rarchives/ripme/tst/Base64Test.java

@@ -1,10 +1,13 @@
 package com.rarchives.ripme.tst;
 
-import junit.framework.TestCase;
 import com.rarchives.ripme.utils.Base64;
+import org.junit.jupiter.api.Test;
 
-public class Base64Test extends TestCase {
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
+public class Base64Test {
+
+    @Test
     public void testDecode() {
         assertEquals("test", new String(Base64.decode("dGVzdA==")));
     }

src/test/java/com/rarchives/ripme/tst/proxyTest.java

@@ -4,14 +4,16 @@ import java.io.IOException;
 import java.net.URL;
 import com.rarchives.ripme.utils.Proxy;
 import com.rarchives.ripme.utils.Utils;
-import junit.framework.TestCase;
 import com.rarchives.ripme.utils.Http;
+import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertFalse;
 
-public class proxyTest  extends TestCase {
+public class proxyTest  {
 
 
     // This test will only run on machines where the user has added a entry for proxy.socks
+    @Test
     public void testSocksProxy() throws IOException {
         // Unset proxy before testing
         System.setProperty("http.proxyHost", "");
@@ -31,6 +33,7 @@ public class proxyTest  extends TestCase {
     }
 
     // This test will only run on machines where the user has added a entry for proxy.http
+    @Test
     public void testHTTPProxy() throws IOException {
         // Unset proxy before testing
         System.setProperty("http.proxyHost", "");