Use Iterator.remove instead of List copy

To point is that when we already know from some paths to be just
regular files, but not directories then at the end we do not need
to check if these are directories. But rather than copying the
list we can use iterators to remove the already discovered files.

src/main/java/io/github/classgraph/ClasspathElementDir.java

@@ -43,6 +43,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Objects;
 import java.util.Set;
@@ -409,11 +410,13 @@ private void scanPathRecursively(final Path path, final LogNode log) {
         // Only scan files in directory if directory is not only an ancestor of an accepted path
         if (parentMatchStatus != ScanSpecPathMatch.ANCESTOR_OF_ACCEPTED_PATH) {
             // Do preorder traversal (files in dir, then subdirs), to reduce filesystem cache misses
-            for (final Path subPath : new ArrayList<>(pathsInDir)) {
+            final Iterator<Path> pathsIterator = pathsInDir.iterator();
+            while (pathsIterator.hasNext()) {
+                final Path subPath = pathsIterator.next();
                 // Process files in dir before recursing
                 BasicFileAttributes fileAttributes = getFileAttributes.get(subPath);
                 if (fileAttributes.isRegularFile()) {
-                    pathsInDir.remove(subPath);
+                    pathsIterator.remove();
                     final Path subPathRelative = classpathEltPath.relativize(subPath);
                     final String subPathRelativeStr = FastPathResolver.resolve(subPathRelative.toString());
                     // If this is a modular jar, ignore all classfiles other than "module-info.class" in the
@@ -452,11 +455,13 @@ private void scanPathRecursively(final Path path, final LogNode log) {
             }
         } else if (scanSpec.enableClassInfo && dirRelativePathStr.equals("/")) {
             // Always check for module descriptor in package root, even if package root isn't in accept
-            for (final Path subPath : new ArrayList<>(pathsInDir)) {
+            final Iterator<Path> pathsIterator = pathsInDir.iterator();
+            while (pathsIterator.hasNext()) {
+                final Path subPath = pathsIterator.next();
                 if (subPath.getFileName().toString().equals("module-info.class")) {
                     BasicFileAttributes fileAttributes = getFileAttributes.get(subPath);
                     if (fileAttributes.isRegularFile()) {
-                        pathsInDir.remove(subPath);
+                        pathsIterator.remove();
                         final Resource resource = newResource(subPath, fileAttributes);
                         addAcceptedResource(resource, parentMatchStatus, /* isClassfileOnly = */ true, subLog);
                         try {