chore(catalog-backend): apply changes required on code review

* apply changes required on code review;
* rephrase the changeset description to be clearer;

Signed-off-by: Valentin VĂLCIU <axiac.ro@gmail.com>

.changeset/tricky-donkeys-wink.md

@@ -2,4 +2,4 @@
 '@backstage/plugin-catalog-backend': patch
 ---
 
-Stop failing on stitching when the entity contains deeply nested properties or long keys.
+Do not fail on stitching when the entity contains `null` values associated to deeply nested or long keys.

plugins/catalog-backend/src/database/operations/stitcher/buildEntitySearch.ts

@@ -133,7 +133,7 @@ export function mapToRows(input: Kv[], entityId: string): DbSearchRow[] {
 
   for (const { key: rawKey, value: rawValue } of input) {
     const key = rawKey.toLocaleLowerCase('en-US');
-    if (MAX_KEY_LENGTH < key.length) {
+    if (key.length > MAX_KEY_LENGTH) {
       continue;
     }
     if (rawValue === undefined || rawValue === null) {