chore(deps): Update dependency net.ltgt.gradle:gradle-nullaway-plugin to v2.1.0 (#531)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

gradle/libs.versions.toml

@@ -63,7 +63,7 @@ build-indra = { module = "net.kyori:indra-common", version.ref = "indra" }
 build-indra-crossdoc = { module = "net.kyori:indra-crossdoc", version.ref = "indra" }
 build-japicmp-plugin = "me.champeau.gradle:japicmp-gradle-plugin:0.4.5"
 build-japicmp = { module = "com.github.siom79.japicmp:japicmp", version.require = "0.23.+" }
-build-nullaway = "net.ltgt.gradle:gradle-nullaway-plugin:2.0.0"
+build-nullaway = "net.ltgt.gradle:gradle-nullaway-plugin:2.1.0"
 build-spotless = { module = "com.diffplug.spotless:spotless-plugin-gradle", version.ref = "spotless" }
 build-shadow = { module = "com.github.johnrengelman:shadow", version = "8.1.1" }