Delete done TODO (#6323)

Author: paulb777

.github/workflows/spm.yml

@@ -13,10 +13,6 @@ on:
 # This workflow builds and tests the Swift Package Manager. Only iOS runs on PRs
 # because each platform takes 15-20 minutes after adding Firestore.
 
-# TODO: Write a script to filter the Package.swift for each individual product
-# and run just those tests in the product specific workflows. Then this workflow
-# should be the full SPM tests for all platforms only on cron.
-
 jobs:
   swift-build-run:
     # Don't run on private repo unless it is a PR.