Make `AllowEncodedSlashes NoDecode` the default

[jamesp-epcc]

At present, this Apache option is set to NoDecode in the server container if the environment variable RUCIO_HTTPD_ENCODED_SLASHES_NO_DECODE is set. To be able to properly fix rucio/rucio#7519 and simplify the parsing of scope and name values sent to the server, we need this to be the default behaviour.