Clarify servlet container compatibility

See gh-34697

Author: matera-jgui

spring-boot-project/spring-boot-docs/src/docs/asciidoc/getting-started/system-requirements.adoc

@@ -37,4 +37,4 @@ Spring Boot supports the following embedded servlet containers:
 | 4.0
 |===
 
-You can also deploy Spring Boot applications to any servlet 3.1+ compatible container.
+You can also deploy Spring Boot applications to any Servlet 3.1 or 4.0 compatible container.