email: fix typo

app/views/notify/new_issue_email.text.erb

 New Issue was created.
 
 Issue <%= @issue.iid %>: <%= url_for(namespace_project_issue_url(@issue.project.namespace, @issue.project, @issue)) %>
-Author:   <%= @issue.author_name %>
-Asignee:  <%= @issue.assignee_name %>
+Author:    <%= @issue.author_name %>
+Assignee:  <%= @issue.assignee_name %>

app/views/notify/new_merge_request_email.text.erb

@@ -3,6 +3,6 @@ New Merge Request #<%= @merge_request.iid %>
 <%= url_for(namespace_project_merge_request_url(@merge_request.target_project.namespace, @merge_request.target_project, @merge_request)) %>
 
 <%= merge_path_description(@merge_request, 'to') %>
-Author:   <%= @merge_request.author_name %>
-Asignee:  <%= @merge_request.assignee_name %>
+Author:    <%= @merge_request.author_name %>
+Assignee:  <%= @merge_request.assignee_name %>