handle Ruby 2.4 Fixnum/Bignum -> Integer deprecations

modules/exploits/multi/misc/java_jdwp_debugger.rb

@@ -229,7 +229,7 @@ class MetasploitModule < Msf::Exploit::Remote
     ret
   end
 
-  # Pack Fixnum for JDWP protocol
+  # Pack Integer for JDWP protocol
   def format(fmt, value)
     if fmt == "L" || fmt == 8
       return [value].pack('Q>')
@@ -240,7 +240,7 @@ class MetasploitModule < Msf::Exploit::Remote
     fail_with(Failure::Unknown, "Unknown format")
   end
 
-  # Unpack Fixnum from JDWP protocol
+  # Unpack Integer from JDWP protocol
   def unformat(fmt, value)
     if fmt == "L" || fmt == 8
       return value[0..7].unpack('Q>')[0]