OTRS - remove DHE ciphers

having DHE-RSA-AES128-GCM-SHA256 & kEDH+AESGCM
was an oversight, copied from production and was removed
there again in I39b389b63ae6b8 (and Ie9badde555d3)

Change-Id: I45d9a44ebe675a292420a6427fda55525023cf7f
Merge "OTRS - remove DHE ciphers" into production