lib/Unicode/UCD.pm: update num() usage example

A combination of two Rumi digits is not considered a valid decimal
number by num() thus resulting in an undef result value. While such
behaviour is properly documented in the num() description and thus
expected, it might be better to give an example that returns a proper
numeric value.

An equivalent change was made to an example in pod/perlunicook.pod.

Author: vaitkus

charclass_invlists.h

@@ -5,7 +5,7 @@ use warnings;
 no warnings 'surrogate';    # surrogates can be inputs to this
 use charnames ();
 
-our $VERSION = '0.78';
+our $VERSION = '0.79';
 
 sub DEBUG () { 0 }
 $|=1 if DEBUG;
@@ -113,7 +113,7 @@ Unicode::UCD - Unicode character database
     my $unicode_version = Unicode::UCD::UnicodeVersion();
 
     my $convert_to_numeric =
-              Unicode::UCD::num("\N{RUMI DIGIT ONE}\N{RUMI DIGIT TWO}");
+              Unicode::UCD::num("\N{VAI DIGIT ONE}\N{VAI DIGIT TWO}");
 
 =head1 DESCRIPTION
 

lib/Unicode/UCD.pm

@@ -452,7 +452,8 @@ convert such strings manually.
  say "@nums";   # 12 4567 0.875 1000000000000
 
  use charnames qw(:full);
- my $nv = num("\N{RUMI DIGIT ONE}\N{RUMI DIGIT TWO}");
+ my $nv = num("\N{VAI DIGIT ONE}\N{VAI DIGIT TWO}");
+ say $nv;  # 12
 
 =head2 ℞ 29: Match Unicode grapheme cluster in regex