Added tests for PhP language server

test/resources/repos/php/test_repo/helper.php

@@ -0,0 +1,7 @@
+<?php
+
+function helperFunction(): void {
+    echo "Helper function was called.";
+}
+
+?> 

test/resources/repos/php/test_repo/index.php

@@ -0,0 +1,16 @@
+<?php
+
+require_once 'helper.php';
+
+function greet(string $name): string {
+    return "Hello, " . $name . "!";
+}
+
+$userName = "PHP User";
+$greeting = greet($userName);
+
+echo $greeting;
+
+helperFunction();
+
+?> 

test/resources/repos/php/test_repo/simple_var.php

@@ -0,0 +1,4 @@
+<?php
+$localVar = "test";
+echo $localVar;
+?>