Fix code scanning alert no. 103: Partial path traversal vulnerability from remote (#216)

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

Author: fugerit79

fj-doc-playground-quarkus/src/main/java/org/fugerit/java/doc/playground/init/ProjectRest.java

@@ -107,7 +107,7 @@ public static String ensureEndWithSlash( String name ) {
     }
     public static void checkIfInTempFolder( File file ) throws IOException {
         File tempDir = new File( System.getProperty("java.io.tmpdir") );
-        if ( !file.getCanonicalPath().startsWith( tempDir.getCanonicalPath() ) ) {
+        if ( !file.toPath().normalize().startsWith(tempDir.toPath().normalize()) ) {
             throw new IOException( file.getCanonicalPath() + " is not in temp folder" );
         }
     }