Update outdated Javadoc links

Fixes #409

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=286092096
diff --git a/core/pom.xml b/core/pom.xml
index e85174f..32bfca7 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -87,8 +87,8 @@
           <docencoding>UTF-8</docencoding>
           <charset>UTF-8</charset>
           <links>
-            <link>https://google.github.io/guava/releases/${guava.version}/api/docs/</link>
-            <link>https://javadoc.io/page/com.google.code.findbugs/jsr305/${jsr305.version}/</link>
+            <link>https://guava.dev/releases/${guava.version}/api/docs/</link>
+            <link>https://javadoc.io/static/com.google.code.findbugs/jsr305/${jsr305.version}/</link>
             <link>https://docs.oracle.com/javase/8/docs/api/</link>
           </links>
         </configuration>