fix(svn): fixed svn ssl support compatability. Fixes #5711

the header downgrade can be eanbled by default as it works on ssl and non ssl.
Make configuration much easier

rhodecode/apps/svn_support/templates/mod-dav-svn.conf.mako

@@ -45,7 +45,7 b''
 % if use_https:
 RequestHeader edit Destination ^https: http: early
 % else:
-#RequestHeader edit Destination ^https: http: early
+RequestHeader edit Destination ^https: http: early
 % endif
 
 <Location "${location_root|n}">

rhodecode/apps/svn_support/tests/test_mod_dav_svn_config.py

@@ -115,5 +115,5 b' class TestModDavSvnConfig(object):'
             assert 'RequestHeader edit Destination ^https: http: early' \
                    in generated_config
         else:
-            assert '#RequestHeader edit Destination ^https: http: early' \
+            assert 'RequestHeader edit Destination ^https: http: early' \
                    in generated_config