Stop using javadoc.io for external Javadoc links

Since our build was failing intermittently, we have decided to stop
using javadoc.io for external Javadoc links for the time being.

build.gradle

@@ -77,15 +77,8 @@ configure([rootProject] + javaProjects) { project ->
 			"https://junit.org/junit4/javadoc/4.13.2/",
 			"https://docs.junit.org/6.0.0/api/",
 			"https://www.reactive-streams.org/reactive-streams-1.0.3-javadoc/",
-			//"https://javadoc.io/static/io.rsocket/rsocket-core/1.1.1/",
 			"https://r2dbc.io/spec/1.0.0.RELEASE/api/",
-			// Previously there could be a split-package issue between JSR250 and JSR305 javax.annotation packages,
-			// but since 6.0 JSR 250 annotations such as @Resource and @PostConstruct have been replaced by their
-			// JakartaEE equivalents in the jakarta.annotation package.
-			//"https://www.javadoc.io/doc/com.google.code.findbugs/jsr305/3.0.2/",
-			"https://jspecify.dev/docs/api/",
-			"https://www.javadoc.io/doc/tools.jackson.core/jackson-databind/3.0.0-rc4/"
-
+			"https://jspecify.dev/docs/api/"
 	] as String[]
 }