`Unescaped left brace in regex is deprecated` warnings

[hakonhagland]

System: Ubuntu 20.04, perl version 5.30.0. The following program:

use strict;
use warnings;
use Syntax::Highlight::Engine::Kate::Perl;
use Term::ANSIColor ':constants';
my $highlighter = Syntax::Highlight::Engine::Kate::Perl->new(
    format_table => {
        'Keyword'      => [ YELLOW,      RESET ],
        'Identifier'   => [ RED,         RESET ],
        'Normal'       => [ WHITE,       RESET ],
        'Operator'     => [ CYAN,        RESET ],
        'String'       => [ MAGENTA,     RESET ],
        'DataType'     => [ CYAN,        RESET ],
    }
);
my $str = 'my $html = qq{<div class="%s">%s</div>};';
my $highlighted = $highlighter->highlightText($str);

produces output:

Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.32), passed through in regex; marked by <-- HERE in m/^({ <-- HERE [^}]+})/ at /home/hakon/perlbrew/perls/perl-5.30.0/lib/site_perl/5.30.0/Syntax/Highlight/Engine/Kate/Template.pm line 850.