fix: npm follower lambda fails on 404 errors (#1689)

the npm follower now makes a GET request for every package it finds.
occasionally, that results in a 404 error. we shouldn't fail the entire
lambda on these, and instead log and move on.

----

*By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache-2.0 license*

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Signed-off-by: github-actions <github-actions@github.com>
Co-authored-by: github-actions <github-actions@github.com>

Author: kaizencc

src/__tests__/__snapshots__/construct-hub.test.ts.snap

@@ -79,9 +79,18 @@ export class CouchChanges extends EventEmitter {
 
     const metadataUrl = new URL(change.id, NPM_REGISTRY_URL);
     console.log(`Fetching metadata for ${change.id}: ${metadataUrl}`);
-    const meta = await this.https('get', metadataUrl);
-    change.doc = meta; // add metadata to the change object
-    return change;
+
+    try {
+      const meta = await this.https('get', metadataUrl);
+      change.doc = meta; // add metadata to the change object
+      return change;
+    } catch (e: any) {
+      if (e.errorMessage.includes('HTTP 404')) {
+        console.log(`Skipping ${change.id} because of 404 error:\n${e}`);
+        return;
+      }
+      throw e;
+    }
   }
 
   private async fetchAndFilterAllMetadata(
@@ -130,9 +139,7 @@ export class CouchChanges extends EventEmitter {
       if (body) {
         headers['Content-Type'] = 'application/json';
       }
-      console.log(
-        `Request: ${method.toUpperCase()} ${url}, ${JSON.stringify(headers)}`
-      );
+
       const req = request(
         url,
         {