fix: use variable in Cache.pm to store memcached max object size

lib/ProductOpener/Cache.pm

@@ -27,6 +27,7 @@ BEGIN {
 	use vars qw(@ISA @EXPORT_OK %EXPORT_TAGS);
 	@EXPORT_OK = qw(
 		$memd
+		$max_memcached_object_size
 		&generate_cache_key
 	);    # symbols to export on request
 	%EXPORT_TAGS = (all => [@EXPORT_OK]);
@@ -52,14 +53,17 @@ $memd = Cache::Memcached::Fast->new(
 	}
 );
 
+# Maximum object size that we can store in memcached
+$max_memcached_object_size = 1048576;
+
 my $json = JSON->new->utf8->allow_nonref->canonical;
 
 =head1 FUNCTIONS
 
 =head2  generate_cache_key($name, $context_ref)
 
 Generate a key to use for caching, that depends on the content of the $context_ref object.
-The key is prependend by the name of the variable we want to store, so that we can set multiple variables for the same context
+The key is prepended by the name of the variable we want to store, so that we can set multiple variables for the same context
 (e.g. a count of search results + the search results themselves)
 
 =head3 Arguments

lib/ProductOpener/Display.pm

@@ -1374,8 +1374,8 @@ sub set_cache_results ($key, $results) {
 	$log->debug("Setting value for MongoDB query key", {key => $key}) if $log->is_debug();
 	my $result_size = total_size($results);
 
-	# memcached max object size is 1 048 576 bytes
-	if ($result_size >= 1048576) {
+	# $max_memcached_object_size is defined is Cache.pm
+	if ($result_size >= $max_memcached_object_size) {
 		$mongodb_log->info(
 			"set_cache_results - skipping - setting value - key: $key (total_size: $result_size > max size)");
 		return;