depend on guava in DependencyConfig

buildSrc/src/main/kotlin/com/dfsek/terra/DependencyConfig.kt

@@ -34,5 +34,8 @@ fun Project.configureDependencies() {
         "testImplementation"("org.junit.jupiter:junit-jupiter-api:5.7.0")
         "testImplementation"("org.junit.jupiter:junit-jupiter-engine:5.7.0")
         "compileOnly"("org.jetbrains:annotations:20.1.0")
+
+        "compileOnly"("com.google.guava:guava:30.0-jre")
+        "testImplementation"("com.google.guava:guava:30.0-jre")
     }
 }