Preserve 'opening_hours' too

re: osmlab/name-suggestion-index#10170 (comment)

These are tags that we want to leave alone (i.e. not offer an "upgrade")
if they already have a value. We assume the mapper knows best.

modules/services/NsiService.js

@@ -234,9 +234,9 @@ export class NsiService extends AbstractSystem {
       // Preserve some tags that we specifically don't want NSI to overwrite. ('^name', sometimes)
       let preserveTags = item.preserveTags || properties.preserveTags || [];
 
-      // These tags can be toplevel tags -or- attributes - so we generally want to preserve existing values - iD#8615
+      // These tags are worth preserving too - see iD#8615
       // We'll only _replace_ the tag value if this tag is the toplevel/defining tag for the matched item (`k`)
-      ['building', 'emergency', 'internet_access', 'takeaway'].forEach(osmkey => {
+      ['building', 'emergency', 'internet_access', 'opening_hours', 'takeaway'].forEach(osmkey => {
         if (k !== osmkey) preserveTags.push(`^${osmkey}$`);
       });