Releases happen from the head branch (#93)

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Author: oleg-nenashev

build.gradle

@@ -190,7 +190,7 @@ publishing {
 
 task checkReleasePreconditions {
   doLast {
-    def REQUIRED_GIT_BRANCH = 'develop'
+    def REQUIRED_GIT_BRANCH = 'HEAD'
     def currentGitBranch = 'git rev-parse --abbrev-ref HEAD'.execute().text.trim()
     assert currentGitBranch == REQUIRED_GIT_BRANCH, "Must be on the $REQUIRED_GIT_BRANCH branch in order to release to Sonatype"
   }