minor #565 [Perplexity] Add API key entry to examples/.env (OskarStark)

This PR was merged into the main branch.

Discussion
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[Perplexity] Add API key entry to `examples/.env`

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| Docs?         | no
| Issues        | --
| License       | MIT

Commits
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a2db19f Add Perplexity API key entry to examples/.env

Author: OskarStark

examples/.env

@@ -87,6 +87,9 @@ GOOGLE_CLOUD_PROJECT=GOOGLE_CLOUD_PROJECT
 ALBERT_API_KEY=
 ALBERT_API_URL=
 
+# Perplexity
+PERPLEXITY_API_KEY=
+
 # For MariaDB store. Server defined in compose.yaml
 MARIADB_URI=pdo-mysql://[email protected]:3309/my_database