Bug 13115 - Holidays.t will fail some unit tests on Sundays

Due to the fact that Sunday is a repeating holiday in the example data
which is used for part but not all of Holidays.t, the last test will
fail on Sundays. The test is to see if today is *not* a special holiday
for MPL, but since it's already a repeating holiday, is_holiday will
return true rather than false.

Test Plan:
1) Wait until Sunday
2) prove t/db_dependent/Holidays.t
3) Note the failure
4) Apply this patch
5) Repeat step 2
6) Note there is no longer a failure

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Used my time machine... :)

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>

t/db_dependent/Holidays.t

@@ -11,6 +11,11 @@ use Test::More tests => 12;
 BEGIN { use_ok('Koha::Calendar'); }
 BEGIN { use_ok('C4::Calendar'); }
 
+my $dbh = C4::Context->dbh();
+# Start transaction
+$dbh->{AutoCommit} = 0;
+$dbh->{RaiseError} = 1;
+
 my $branchcode = 'MPL';
 
 my $koha_calendar = Koha::Calendar->new( branchcode => $branchcode );
@@ -45,6 +50,9 @@ is( $koha_calendar->is_holiday($monday),    0, 'Monday is not a closed day' );
 is( $koha_calendar->is_holiday($christmas), 1, 'Christmas is a closed day' );
 is( $koha_calendar->is_holiday($newyear), 1, 'New Years day is a closed day' );
 
+$dbh->do("DELETE FROM repeatable_holidays");
+$dbh->do("DELETE FROM special_holidays");
+
 my $custom_holiday = DateTime->new(
     year  => 2013,
     month => 11,