Update links to https [ci skip]

Ref. heartcombo#5833

Author: carlosantoniodasilva

CODE_OF_CONDUCT.md

@@ -19,4 +19,4 @@ This code of conduct applies both within project spaces and in public spaces whe
 
 Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by sending an email to [heartcombo.oss@gmail.com](heartcombo.oss@gmail.com) or contacting one or more of the project maintainers.
 
-This Code of Conduct is adapted from the [Contributor Covenant](http://contributor-covenant.org), version 1.2.0, available at [http://contributor-covenant.org/version/1/2/0/](http://contributor-covenant.org/version/1/2/0/)
+This Code of Conduct is adapted from the [Contributor Covenant](https://contributor-covenant.org), version 1.2.0, available at [https://contributor-covenant.org/version/1/2/0/](https://contributor-covenant.org/version/1/2/0/)

CONTRIBUTING.md

@@ -27,7 +27,7 @@ internationalization.
 
 Avoid opening new issues to ask questions in our issues tracker. Please go through
 the project wiki, documentation and source code first, or try to ask your question
-on [Stack Overflow](http://stackoverflow.com/questions/tagged/devise).
+on [Stack Overflow](https://stackoverflow.com/questions/tagged/devise).
 
 **If you find a security bug, do not report it through GitHub. Please send an
 e-mail to [heartcombo.oss@gmail.com](mailto:heartcombo.oss@gmail.com)

README.md

@@ -79,7 +79,7 @@ If you have discovered a security related bug, please do *NOT* use the GitHub is
 
 If you have any questions, comments, or concerns, please use StackOverflow instead of the GitHub issue tracker:
 
-http://stackoverflow.com/questions/tagged/devise
+https://stackoverflow.com/questions/tagged/devise
 
 The deprecated mailing lists can still be read on:
 
@@ -90,7 +90,7 @@ https://groups.google.com/group/heartcombo
 
 You can view the Devise documentation in RDoc format here:
 
-http://rubydoc.info/github/heartcombo/devise/main/frames
+https://rubydoc.info/github/heartcombo/devise/main/frames
 
 If you need to use Devise with previous versions of Rails, you can always run "gem server" from the command line after you install the gem to access the old documentation.
 
@@ -745,7 +745,7 @@ config.http_authenticatable = [:database]
 ```
 
 This restriction does not limit you from implementing custom warden strategies, either in your application or via gem-based extensions for devise.
-A common authentication strategy for APIs is token-based authentication. For more information on extending devise to support this type of authentication and others, see the wiki article for [Simple Token Authentication Examples and alternatives](https://github.com/heartcombo/devise/wiki/How-To:-Simple-Token-Authentication-Example#alternatives) or this blog post on [Custom authentication methods with Devise](http://blog.plataformatec.com.br/2019/01/custom-authentication-methods-with-devise/).
+A common authentication strategy for APIs is token-based authentication. For more information on extending devise to support this type of authentication and others, see the wiki article for [Simple Token Authentication Examples and alternatives](https://github.com/heartcombo/devise/wiki/How-To:-Simple-Token-Authentication-Example#alternatives) or this blog post on [Custom authentication methods with Devise](https://blog.plataformatec.com.br/2019/01/custom-authentication-methods-with-devise/).
 
 #### Testing
 API Mode changes the order of the middleware stack, and this can cause problems for `Devise::Test::IntegrationHelpers`. This problem usually surfaces as an ```undefined method `[]=' for nil:NilClass``` error when using integration test helpers, such as `#sign_in`. The solution is simply to reorder the middlewares by adding the following to test.rb: