use less violent language

packages/kbn-optimizer/src/node/cache.ts

@@ -81,12 +81,12 @@ export class Cache {
       encoding: 'msgpack',
     });
 
-    // after the process has been running for 30 minutes cull the
+    // after the process has been running for 30 minutes prune the
     // keys which haven't been used in 30 days. We use `unref()` to
     // make sure this timer doesn't hold other processes open
     // unexpectedly
     setTimeout(() => {
-      this.cullOldKeys();
+      this.pruneOldKeys();
     }, 30 * MINUTE).unref();
   }
 
@@ -124,7 +124,7 @@ export class Cache {
     return `${this.prefix}${path}`;
   }
 
-  private async cullOldKeys() {
+  private async pruneOldKeys() {
     try {
       const ATIME_LIMIT = Date.now() - 30 * DAY;
       const BATCH_SIZE = 1000;