Maintenance: Update dependency telephone_number to v1.4.21

Gemfile.lock

@@ -628,7 +628,7 @@ GEM
       faraday (~> 2.0)
       faraday-multipart (~> 1.0)
       zeitwerk (~> 2.6)
-    telephone_number (1.4.20)
+    telephone_number (1.4.21)
     terser (1.2.0)
       execjs (>= 0.3.0, < 3)
     test-unit (3.6.2)