Bump Guava to 33.4.8.

RELNOTES=n/a
PiperOrigin-RevId: 747504024

Author: cpovirk

pom.xml

@@ -66,7 +66,7 @@
     <dependency>
       <groupId>com.google.guava</groupId>
       <artifactId>guava</artifactId>
-      <version>33.4.7-jre</version>
+      <version>33.4.8-jre</version>
     </dependency>
     <dependency>
       <groupId>com.google.errorprone</groupId>