Bump gradle-nexus-staging-plugin from 0.8.0 to 0.21.2

Bumps [gradle-nexus-staging-plugin](https://github.com/Codearte/gradle-nexus-staging-plugin) from 0.8.0 to 0.21.2.
- [Release notes](https://github.com/Codearte/gradle-nexus-staging-plugin/releases)
- [Changelog](https://github.com/Codearte/gradle-nexus-staging-plugin/blob/master/CHANGELOG.md)
- [Commits](Codearte/gradle-nexus-staging-plugin@release/0.8.0...release/0.21.2)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

build.gradle

@@ -8,7 +8,7 @@ buildscript {
         classpath "com.jfrog.bintray.gradle:gradle-bintray-plugin:1.8.5"
         classpath "com.netflix.nebula:gradle-extra-configurations-plugin:2.2.0"
         classpath 'com.bmuschko:gradle-nexus-plugin:2.3.1'
-        classpath "io.codearte.gradle.nexus:gradle-nexus-staging-plugin:0.8.0"
+        classpath "io.codearte.gradle.nexus:gradle-nexus-staging-plugin:0.21.2"
         classpath "io.github.groovylang.groovydoc:groovydoc-gradle-plugin:1.0.1"
     }
 }