refactor: optimize imports for import action

Author: codescape

src/main/java/de/codescape/jira/plugins/multiplesubtasks/action/SubtaskTemplateImportAction.java

@@ -30,7 +30,6 @@
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.StringWriter;
-import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;