URL Cleanup

This commit updates URLs to prefer the https protocol. Redirects are not followed to avoid accidentally expanding intentionally shortened URLs (i.e. if using a URL shortener).

# Fixed URLs

## Fixed Success
These URLs were switched to an https URL with a 2xx status. While the status was successful, your review is still recommended.

* [ ] http://beanvalidation.org/ with 1 occurrences migrated to:
  https://beanvalidation.org/ ([https](https://beanvalidation.org/) result 200).
* [ ] http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/ with 1 occurrences migrated to:
  https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/ ([https](https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/) result 200).
* [ ] http://github.com/spring-projects/spring-shell with 1 occurrences migrated to:
  https://github.com/spring-projects/spring-shell ([https](https://github.com/spring-projects/spring-shell) result 200).
* [ ] http://start.spring.io with 2 occurrences migrated to:
  https://start.spring.io ([https](https://start.spring.io) result 200).
* [ ] http://www.java.com/en/download/help/error_hotspot.xml with 1 occurrences migrated to:
  https://www.java.com/en/download/help/error_hotspot.xml ([https](https://www.java.com/en/download/help/error_hotspot.xml) result 200).
* [ ] http://contributor-covenant.org with 1 occurrences migrated to:
  https://contributor-covenant.org ([https](https://contributor-covenant.org) result 301).
* [ ] http://contributor-covenant.org/version/1/3/0/ with 1 occurrences migrated to:
  https://contributor-covenant.org/version/1/3/0/ ([https](https://contributor-covenant.org/version/1/3/0/) result 301).

Author: spring-operator

CODE_OF_CONDUCT.adoc

@@ -40,5 +40,5 @@ appropriate to the circumstances. Maintainers are obligated to maintain confiden
 with regard to the reporter of an incident.
 
 This Code of Conduct is adapted from the
-http://contributor-covenant.org[Contributor Covenant], version 1.3.0, available at
-http://contributor-covenant.org/version/1/3/0/[contributor-covenant.org/version/1/3/0/]
+https://contributor-covenant.org[Contributor Covenant], version 1.3.0, available at
+https://contributor-covenant.org/version/1/3/0/[contributor-covenant.org/version/1/3/0/]

spring-shell-docs/src/main/asciidoc/using-spring-shell.adoc

@@ -11,7 +11,7 @@ Starting with version 2, Spring Shell has been rewritten from the ground up with
 enhancements in mind, one of which is easy integration with Spring Boot, although it is
 not a strong requirement.
 For the purpose of this tutorial, let's create a simple Boot application, for example
-using http://start.spring.io. This minimal application only depends on `spring-boot-starter`
+using https://start.spring.io. This minimal application only depends on `spring-boot-starter`
 and configures the `spring-boot-maven-plugin`, generating an executable über-jar:
 
 [source, xml]
@@ -45,7 +45,7 @@ configuring only the necessary beans as needed:
 ====
 Given that Spring Shell will kick in and start the REPL by virtue of this dependency being present,
 you'll need to either build skipping tests (`-DskipTests`) throughout this tutorial or remove the sample integration test
-that was generated by http://start.spring.io. If you don't do so, the integration test will create
+that was generated by https://start.spring.io. If you don't do so, the integration test will create
 the Spring `ApplicationContext` and, depending on your build tool, will stay stuck in the eval loop or crash with a NPE.
 ====
 
@@ -86,7 +86,7 @@ java -jar target/demo-0.0.1-SNAPSHOT.jar
 ----
 
 You'll be greeted by the following screen (the banner comes from Spring Boot, and can be customized
-http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#boot-features-banner[as usual]):
+https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#boot-features-banner[as usual]):
 
 [source]
 ----
@@ -451,7 +451,7 @@ TBD
 [[validating-command-arguments]]
 === Validating Command Arguments
 
-Spring Shell integrates with the http://beanvalidation.org/[Bean Validation API] to support
+Spring Shell integrates with the https://beanvalidation.org/[Bean Validation API] to support
 automatic and self documenting constraints on command parameters.
 
 Annotations found on command parameters as well as annotations at the method level will be
@@ -814,7 +814,7 @@ public class MyClear implements Clear.Command {
 .Please Consider Contributing your Changes
 ====
 If you feel like your implementation of a standard command could be valuable to the community,
-please consider opening a pull-request at http://github.com/spring-projects/spring-shell.
+please consider opening a pull-request at https://github.com/spring-projects/spring-shell.
 
 Alternatively, before making any changes on your own, you can open an issue with the project. Feedback is
 always welcome!

spring-shell-test-samples/.gitignore

@@ -115,7 +115,7 @@ xcuserdata/
 *.war
 *.ear
 
-# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+# virtual machine crash logs, see https://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
 
 ## Eclipse