Bump com.gradle.plugin-publish from 2.1.0 to 2.1.1

Bumps com.gradle.plugin-publish from 2.1.0 to 2.1.1.

---
updated-dependencies:
- dependency-name: com.gradle.plugin-publish
  dependency-version: 2.1.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

build.gradle

@@ -1,5 +1,5 @@
 plugins {
-    id 'com.gradle.plugin-publish' version '2.1.0'
+    id 'com.gradle.plugin-publish' version '2.1.1'
     id 'java-gradle-plugin'
     id 'groovy'
     id 'jacoco'