fix(backend): fix type error(s) in security fixes (#15009)

* Fix type error in security fixes

(cherry picked from commit fa3cf6c2996741e642955c5e2fca8ad785e83205)

* Fix error in test function calls

(cherry picked from commit 1758f29364eca3cbd13dbb5c84909c93712b3b3b)

* Fix style error

(cherry picked from commit 23c4aa25714af145098baa7edd74c1d217e51c1a)

* Fix another style error

(cherry picked from commit 36af07abe28bec670aaebf9f5af5694bb582c29a)

* Fix `.punyHost` misuse

(cherry picked from commit 6027b516e1c82324d55d6e54d0e17cbd816feb42)

* attempt to fix test: make yaml valid

---------

Co-authored-by: Julia Johannesen <julia@insertdomain.name>

packages/backend/test-federation/.config/example.default.yml

@@ -19,7 +19,6 @@ proxyBypassHosts:
   - challenges.cloudflare.com
 proxyRemoteFiles: true
 signToActivityPubGet: true
-allowedPrivateNetworks: [
-  '127.0.0.1/32',
-  '172.20.0.0/16'
-]
+allowedPrivateNetworks:
+  - 127.0.0.1/32
+  - 172.20.0.0/16