introduce proper code indentation in examples

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You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/4278

-- Commit Summary --

* rtpengine: fix formatting of subscribe/unsubscribe examples

-- File Changes --

M src/modules/rtpengine/doc/rtpengine_admin.xml (153)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/4278.patch https://github.com/kamailio/kamailio/pull/4278.diff