Update rails to 6.0.4.3 (from 6.0.4.1)

in response to a bundle audit

Name: actionpack
Version: 6.0.4.1
Advisory: CVE-2021-44528
Criticality: Unknown
URL: https://groups.google.com/g/ruby-security-ann/c/vG9gz3nk1pM/m/7-NU4MNrDAAJ
Title: Possible Open Redirect in Host Authorization Middleware
Solution: upgrade to ~> 6.0.4, >= 6.0.4.2, ~> 6.1.4, >= 6.1.4.2, >= 7.0.0.rc2
Vulnerabilities found!