style: fix checkstyle violations in ValidParentheses and tests

Author: Ruturaj-007

src/main/java/com/thealgorithms/stacks/ValidParentheses.java

@@ -44,9 +44,9 @@ public static boolean isValid(final String str) {
                     return false;
                 }
                 char top = stack.peek();
-                if ((top == '(' && ch == ')') ||
-                        (top == '{' && ch == '}') ||
-                        (top == '[' && ch == ']')) {
+                if ((top == '(' && ch == ')')
+                        || (top == '{' && ch == '}')
+                        || (top == '[' && ch == ']')) {
                     stack.pop();
                 } else {
                     return false;

src/test/java/com/thealgorithms/stacks/ValidParenthesesTest.java

@@ -2,8 +2,6 @@
 
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 import java.util.stream.Stream;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
@@ -13,7 +11,7 @@ public class ValidParenthesesTest {
 
     @ParameterizedTest
     @MethodSource("provideValidTestCases")
-    void testIsValid_ValidCases(String input, boolean expected) {
+    void testIsValidValidCases(String input, boolean expected) {
         assertEquals(expected, ValidParentheses.isValid(input));
     }
 
@@ -28,7 +26,7 @@ static Stream<Arguments> provideValidTestCases() {
 
     @ParameterizedTest
     @MethodSource("provideInvalidTestCases")
-    void testIsValid_InvalidCases(String input) {
+    void testIsValidInvalidCases(String input) {
         assertEquals(false, ValidParentheses.isValid(input));
     }