perf: use git tag --merge <branch> to filter tags present in a branch history

BREAKING CHANGE: Git CLI version 2.7.1 or higher is now required

The `--merge` option of the `git tag` command has been added in Git version 2.7.1 and is now used by semantic-release

bin/semantic-release.js

@@ -10,7 +10,7 @@ var execa = require('execa');
 var findVersions = require('find-versions');
 var pkg = require('../package.json');
 
-var MIN_GIT_VERSION = '2.0.0';
+var MIN_GIT_VERSION = '2.7.1';
 
 if (!semver.satisfies(process.version, pkg.engines.node)) {
   console.error(