Fix unmatched quotation (#251)

lkmpg.tex

@@ -190,7 +190,7 @@ \subsection{Before We Begin}
         If this message \emph{Lockdown: insmod: unsigned module loading is restricted;
         see man kernel lockdown.7} appears in the \sh|dmesg| output,
         the simplest approach involves disabling UEFI SecureBoot from the boot menu of your PC or laptop,
-        allowing the successful insertion of `hello world'' module.
+        allowing the successful insertion of ``hello world'' module.
         Naturally, an alternative involves undergoing intricate procedures such as generating keys, system key installation,
         and module signing to achieve functionality.
         However, this intricate process is less appropriate for beginners. If interested,