Streamline XML namespace support towards unversioned schemas

This commit also removes support code for outdated options which were only available in older schema versions.

Issue: SPR-13499

Author: jhoeller

spring-aop/src/main/resources/META-INF/spring.schemas

@@ -1,10 +1,10 @@
-http\://www.springframework.org/schema/aop/spring-aop-2.0.xsd=org/springframework/aop/config/spring-aop-2.0.xsd
-http\://www.springframework.org/schema/aop/spring-aop-2.5.xsd=org/springframework/aop/config/spring-aop-2.5.xsd
-http\://www.springframework.org/schema/aop/spring-aop-3.0.xsd=org/springframework/aop/config/spring-aop-3.0.xsd
-http\://www.springframework.org/schema/aop/spring-aop-3.1.xsd=org/springframework/aop/config/spring-aop-3.1.xsd
-http\://www.springframework.org/schema/aop/spring-aop-3.2.xsd=org/springframework/aop/config/spring-aop-3.2.xsd
-http\://www.springframework.org/schema/aop/spring-aop-4.0.xsd=org/springframework/aop/config/spring-aop-4.0.xsd
-http\://www.springframework.org/schema/aop/spring-aop-4.1.xsd=org/springframework/aop/config/spring-aop-4.1.xsd
-http\://www.springframework.org/schema/aop/spring-aop-4.2.xsd=org/springframework/aop/config/spring-aop-4.2.xsd
-http\://www.springframework.org/schema/aop/spring-aop-4.3.xsd=org/springframework/aop/config/spring-aop-4.3.xsd
-http\://www.springframework.org/schema/aop/spring-aop.xsd=org/springframework/aop/config/spring-aop-4.3.xsd
+http\://www.springframework.org/schema/aop/spring-aop-2.0.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-2.5.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-3.0.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-3.1.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-3.2.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-4.0.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-4.1.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-4.2.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop-4.3.xsd=org/springframework/aop/config/spring-aop.xsd
+http\://www.springframework.org/schema/aop/spring-aop.xsd=org/springframework/aop/config/spring-aop.xsd