Bump flexsearch to ^0.8.164 (#46121)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

docs/package.json

@@ -70,7 +70,7 @@
     "feed": "^4.2.2",
     "fg-loadcss": "^3.1.0",
     "final-form": "^4.20.10",
-    "flexsearch": "^0.8.158",
+    "flexsearch": "^0.8.164",
     "fs-extra": "^11.3.0",
     "json2mq": "^0.2.0",
     "jss": "^10.10.0",