software/seleniumserver: remove useless bytes= for password recipes

the default bytes is just fine

software/seleniumserver/buildout.hash.cfg

@@ -19,4 +19,4 @@ md5sum = 10e19df182c692b71ea552da183a0bcf
 
 [template-selenium]
 filename = instance-selenium.cfg.in
-md5sum = 389766d95744b80fdc80a10cdde9551c
+md5sum = 8c48c7bef34dd54ab3bd94c91f2bf041

software/seleniumserver/instance-selenium.cfg.in

@@ -137,12 +137,10 @@ port = 7782
 [selenium-server-admin-password]
 recipe = slapos.cookbook:generate.password
 username = admin
-bytes = 12
 
 [selenium-server-selenium-password]
 recipe = slapos.cookbook:generate.password
 username = selenium
-bytes = 12
 
 
 [selenium-server-frontnend-certificate]