Fix Hello World examples and add Python test

HelloWorld.py

@@ -1,2 +1,3 @@
 #!/usr/bin/python3
-print("Hello,world!")
+# Prints "Hello, World!" to the console
+print("Hello, World!")

Helloworld.cpp

@@ -1,5 +1,5 @@
-#include <bits/stdc++.h>
+#include <iostream>
 int main (){
-    std:: cout << "Hello,World!" << std:: endl;
+    std::cout << "Hello, World!" << std::endl;
     return 0;
 }

README.md

@@ -1,2 +1,2 @@
-# Hello-World-
-My first repository in Github
+# Hello World
+My first repository on GitHub. A collection of Hello World programs in various languages.

tests/test_hello.py

@@ -0,0 +1,6 @@
+import subprocess
+import sys
+
+def test_python_output():
+    result = subprocess.run([sys.executable, "HelloWorld.py"], capture_output=True, text=True, check=True)
+    assert result.stdout.strip() == "Hello, World!"