Migrate from master to main.

README.adoc

@@ -26,9 +26,9 @@ the server will push a greeting into a queue to which the client is subscribed.
 == What You Need
 
 :java_version: 1.8
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+include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/main/prereq_editor_jdk_buildtools.adoc[]
 
-include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/master/how_to_complete_this_guide.adoc[]
+include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/main/how_to_complete_this_guide.adoc[]
 
 [[scratch]]
 == Starting with Spring Initializr
@@ -324,11 +324,11 @@ include::complete/src/main/java/com/example/messagingstompwebsocket/MessagingSto
 ----
 ====
 
-include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/master/spring-boot-application-new-path.adoc[]
+include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/main/spring-boot-application-new-path.adoc[]
 
-include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/master/build_an_executable_jar_subhead.adoc[]
+include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/main/build_an_executable_jar_subhead.adoc[]
 
-include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/master/build_an_executable_jar_with_both.adoc[]
+include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/main/build_an_executable_jar_with_both.adoc[]
 
 
 Logging output is displayed. The service should be up and running within a few seconds.
@@ -354,4 +354,4 @@ The following guides may also be helpful:
 * https://spring.io/guides/gs/serving-web-content/[Serving Web Content with Spring MVC]
 * https://spring.io/guides/gs/spring-boot/[Building an Application with Spring Boot]
 
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+include::https://raw.githubusercontent.com/spring-guides/getting-started-macros/main/footer.adoc[]