Bump net.ltgt.gradle:gradle-nullaway-plugin from 2.0.0 to 2.1.0 (#3921)

Author: dependabot[bot]

buildSrc/build.gradle.kts

@@ -36,7 +36,7 @@ dependencies {
   implementation("io.opentelemetry.instrumentation:gradle-plugins:2.8.0-alpha")
 
   implementation("net.ltgt.gradle:gradle-errorprone-plugin:4.1.0")
-  implementation("net.ltgt.gradle:gradle-nullaway-plugin:2.0.0")
+  implementation("net.ltgt.gradle:gradle-nullaway-plugin:2.1.0")
 
   implementation("gradle.plugin.io.morethan.jmhreport:gradle-jmh-report:0.9.6")
   implementation("me.champeau.jmh:jmh-gradle-plugin:0.7.2")