Allow multiple digits in Vagrant 2.x minor versions

This commit allows the minor version in Vagrant 2.x versions to have two
digits when we perform the Vagrant version check.

buildSrc/src/main/groovy/org/elasticsearch/gradle/vagrant/VagrantSupportPlugin.groovy

@@ -45,7 +45,7 @@ class VagrantSupportPlugin implements Plugin<Project> {
             }
             String version = pipe.toString().trim()
             if (runResult.exitValue == 0) {
-                if (version ==~ /Vagrant 1\.(8\.[6-9]|9\.[0-9])+/ || version ==~ /Vagrant 2\.[0-9]\.[0-9]+/) {
+                if (version ==~ /Vagrant 1\.(8\.[6-9]|9\.[0-9])+/ || version ==~ /Vagrant 2\.[0-9]+\.[0-9]+/) {
                     return [ 'supported' : true ]
                 } else {
                     return [ 'supported' : false,