Remove support for Resin Servlet container

This commit removes all references to the Resin Servlet container, as it
is not supported as of Spring Framework 6.0 because we require a
JakartaEE baseline.

Closes gh-33772

framework-docs/modules/ROOT/pages/data-access/orm/jpa.adoc

@@ -142,8 +142,7 @@ Alternatively, specify a custom `persistenceXmlLocation` on your
 META-INF/my-persistence.xml) and include only a descriptor with that name in your
 application jar files. Because the Jakarta EE server looks only for default
 `META-INF/persistence.xml` files, it ignores such custom persistence units and, hence,
-avoids conflicts with a Spring-driven JPA setup upfront. (This applies to Resin 3.1, for
-example.)
+avoids conflicts with a Spring-driven JPA setup upfront.
 
 .When is load-time weaving required?
 ****

framework-docs/modules/ROOT/pages/web/webmvc/mvc-config/default-servlet-handler.adoc

@@ -21,7 +21,7 @@ The caveat to overriding the `/` Servlet mapping is that the `RequestDispatcher`
 default Servlet must be retrieved by name rather than by path. The
 `DefaultServletHttpRequestHandler` tries to auto-detect the default Servlet for
 the container at startup time, using a list of known names for most of the major Servlet
-containers (including Tomcat, Jetty, GlassFish, JBoss, Resin, WebLogic, and WebSphere).
+containers (including Tomcat, Jetty, GlassFish, JBoss, WebLogic, and WebSphere).
 If the default Servlet has been custom-configured with a different name, or if a
 different Servlet container is being used where the default Servlet name is unknown,
 then you must explicitly provide the default Servlet's name, as the following example shows: