Add deadline

wiki/src/jobs/technical_writer.mdwn

@@ -16,6 +16,8 @@ for writing our user documentation, support pages, and release notes.
 
 This is a paid offer for self-employed freelancers.
 
+**Deadline for applications: June 30**
+
 About Tails
 ===========
 
@@ -120,7 +122,7 @@ Additionally, we would love it if you have:
 How to apply
 ============
 
-Send an email to <sajolida@pimienta.org>.
+Send an email to <sajolida@pimienta.org> until June 30.
 
 <style>
 .apply-cover-letter, .apply-contributions { display: none; }