LibPDF: Allow text operator sequences to start with whitespace

Author: https://github.com/janso3
Commit: 2f71e0f09a
Pull-request: https://github.com/SerenityOS/serenity/pull/15270
Reviewed-by: https://github.com/ADKaster
Reviewed-by: https://github.com/gmta
Reviewed-by: https://github.com/mattco98

Userland/Libraries/LibPDF/Parser.cpp

@@ -496,6 +496,8 @@ PDFErrorOr<Vector<Operator>> Parser::parse_operators()
         return isalpha(ch) || ch == '*' || ch == '\'';
     };
 
+    m_reader.consume_whitespace();
+
     while (!m_reader.done()) {
         auto ch = m_reader.peek();
         if (is_operator_char(ch)) {